This reverts commit 809ed88.

* Revert "Revert "perf: close sessions async (#24)" (#43)"

This reverts commit 809ed88.

* Ignore compatibility check failure in internal interfaces.

asyncClose() was added to com.google.cloud.spanner.Session and
asyncDeleteSession() was added to
com.google.cloud.spanner.spi.v1.SpannerRpc in #24 which resulted in
binary compatibility test failures. This config allows us to ignore the
failure.

* Annotate SpannerRpc and Session classes as @internalapi.

Users shouldn't be implementing these interfaces as they're internal to
the client library implementation.

🤖 I have created a release \*beep\* \*boop\* 
---
## [1.14.0](https://www..com/googleapis/java-spanner-jdbc/compare/v1.13.0...v1.14.0) (2020-03-18)


### Features

* add support for foreign keys ([googleapis#78](https://www..com/googleapis/java-spanner-jdbc/issues/78)) ([9e770f2](https://www..com/googleapis/java-spanner-jdbc/commit/9e770f281c03a1e9c034e5ff3ddee44fa20a7b30)), closes [googleapis#77](https://www..com/googleapis/java-spanner-jdbc/issues/77)


### Bug Fixes

* add missing netty-shaded lib for über-jar ([googleapis#80](https://www..com/googleapis/java-spanner-jdbc/issues/80)) ([3d6f356](https://www..com/googleapis/java-spanner-jdbc/commit/3d6f35669671194e6772fe327ce48f27e5bf4643))
* fix deprecation warnings in JDBC (test) files ([googleapis#81](https://www..com/googleapis/java-spanner-jdbc/issues/81)) ([a5e031d](https://www..com/googleapis/java-spanner-jdbc/commit/a5e031d3183f8fe88a621500f235ca2b0242f50b))
* include Spanner gRPC test dependencies ([googleapis#63](https://www..com/googleapis/java-spanner-jdbc/issues/63)) ([a34bfc0](https://www..com/googleapis/java-spanner-jdbc/commit/a34bfc0ff1c2ddeef077dbfae4c56bdd53febcb2))


### Dependencies

* update core dependencies ([1ae098e](https://www..com/googleapis/java-spanner-jdbc/commit/1ae098e924c2a488cfddd0a3aee9511274b7a515))
* update core dependencies ([googleapis#40](https://www..com/googleapis/java-spanner-jdbc/issues/40)) ([18c3a1b](https://www..com/googleapis/java-spanner-jdbc/commit/18c3a1b069cb507a91d0320e64a8bf8ae8efe394))
* update core dependencies ([googleapis#73](https://www..com/googleapis/java-spanner-jdbc/issues/73)) ([cfa1539](https://www..com/googleapis/java-spanner-jdbc/commit/cfa153997599c36f1243e87f1ea0760694657dfe))
* update core dependencies to v1.27.1 ([googleapis#61](https://www..com/googleapis/java-spanner-jdbc/issues/61)) ([181991b](https://www..com/googleapis/java-spanner-jdbc/commit/181991bda1f66de707d27dad9658b9177626595a))
* update core dependencies to v1.27.2 ([googleapis#71](https://www..com/googleapis/java-spanner-jdbc/issues/71)) ([12425fc](https://www..com/googleapis/java-spanner-jdbc/commit/12425fcb4382449e4a7a0edad4c812b7ce15aa71))
* update core dependencies to v1.54.0 ([googleapis#72](https://www..com/googleapis/java-spanner-jdbc/issues/72)) ([5676021](https://www..com/googleapis/java-spanner-jdbc/commit/567602177e05fa198eaa011fbca05cfe4b72fb13))
* update core dependencies to v1.92.5 ([googleapis#53](https://www..com/googleapis/java-spanner-jdbc/issues/53)) ([604ee2b](https://www..com/googleapis/java-spanner-jdbc/commit/604ee2b75204ad52eaf724c3fb71e8c13540af7c))
* update core transport dependencies to v1.34.1 ([googleapis#43](https://www..com/googleapis/java-spanner-jdbc/issues/43)) ([2b6f04d](https://www..com/googleapis/java-spanner-jdbc/commit/2b6f04da3aeebac778fb664c4564fb8b58bf3be4))
* update core transport dependencies to v1.34.2 ([googleapis#62](https://www..com/googleapis/java-spanner-jdbc/issues/62)) ([8739015](https://www..com/googleapis/java-spanner-jdbc/commit/8739015f62289adb92fd55b19a5bff8762da20a9))
* update dependency com.google.api-client:google-api-client-bom to v1.30.8 ([googleapis#46](https://www..com/googleapis/java-spanner-jdbc/issues/46)) ([ef891b0](https://www..com/googleapis/java-spanner-jdbc/commit/ef891b000045d1f39f91b6a0ed3abaab19c5f05e))
* update dependency com.google.api-client:google-api-client-bom to v1.30.9 ([googleapis#74](https://www..com/googleapis/java-spanner-jdbc/issues/74)) ([3b62299](https://www..com/googleapis/java-spanner-jdbc/commit/3b622999b9f9645a6086e5efd3206f4d7b0806bc))
* update dependency com.google.truth:truth to v1.0.1 ([googleapis#32](https://www..com/googleapis/java-spanner-jdbc/issues/32)) ([5205863](https://www..com/googleapis/java-spanner-jdbc/commit/52058636e10951e883523204f0f161db8a972d62))
* update protobuf.version to v3.11.3 ([googleapis#48](https://www..com/googleapis/java-spanner-jdbc/issues/48)) ([0779fcb](https://www..com/googleapis/java-spanner-jdbc/commit/0779fcb0bfe935c3c302fa8442f733c7e3629761))
* update protobuf.version to v3.11.4 ([googleapis#64](https://www..com/googleapis/java-spanner-jdbc/issues/64)) ([f485cff](https://www..com/googleapis/java-spanner-jdbc/commit/f485cfffa0de27ce35f5d16c689c31c6ea22138e))
* update spanner.version to v1.51.0 ([googleapis#75](https://www..com/googleapis/java-spanner-jdbc/issues/75)) ([4fff168](https://www..com/googleapis/java-spanner-jdbc/commit/4fff168eae61fb55933cf3afd67f24ca65dfde54))
---


This PR was generated with [Release Please](https://.com/googleapis/release-please).