* chore(ci): fix typo in restrict presubmit samples ITs to only snapshot

Fixes below error in Java repos when googleapis/synthtool#804 was merged:
```
/java-bigquerystorage/.kokoro/build.sh: line 81: pushd: {SAMPLES_DIR}: No such file or directory
```

Thanks @kolea2 for spotting this in Fusion build logs.

cc @chingor13

Source-Author: Stephanie Wang <[email protected]>
Source-Date: Mon Oct 26 13:44:04 2020 -0400
Source-Repo: googleapis/synthtool
Source-Sha: f68649c5f26bcff6817c6d21e90dac0fc71fef8e
Source-Link: googleapis/synthtool@f68649c

* chore(java): enable generated-files-bot

This bot will comment on pull requests that modify templated files. For java, we configure to read from our 2 synth.metadata files: (primary templates and README)

Source-Author: Jeff Ching <[email protected]>
Source-Date: Fri Oct 30 14:22:02 2020 -0700
Source-Repo: googleapis/synthtool
Source-Sha: b19b401571e77192f8dd38eab5fb2300a0de9324
Source-Link: googleapis/synthtool@b19b401

🤖 I have created a release \*beep\* \*boop\* 
---
### Updating meta-information for bleeding-edge SNAPSHOT release.
---


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

Source-Author: Les Vogel <[email protected]>
Source-Date: Wed Nov 4 10:18:01 2020 -0800
Source-Repo: googleapis/synthtool
Source-Sha: c7824ea48ff6d4d42dfae0849aec8a85acd90bd9
Source-Link: googleapis/synthtool@c7824ea

… to v1.38.0 (#207)

🤖 I have created a release \*beep\* \*boop\* 
---
## [0.15.0](https://www..com/googleapis/java-shared-dependencies/compare/0.14.1...v0.15.0) (2020-11-10)


### Dependencies

* update dependency com.google.http-client:google-http-client-bom to v1.38.0 ([#207](https://www..com/googleapis/java-shared-dependencies/issues/207)) ([5e3198d](https://www..com/googleapis/java-shared-dependencies/commit/5e3198de5e1d0fe55c4d947b12984db7726059da))
* update google.common-protos.version to v2.0.1 ([#205](https://www..com/googleapis/java-shared-dependencies/issues/205)) ([6b12417](https://www..com/googleapis/java-shared-dependencies/commit/6b1241737d34e99a55acdcd439aa71ad28d1e26c))
* update iam.version to v1.0.3 ([#206](https://www..com/googleapis/java-shared-dependencies/issues/206)) ([94a4e31](https://www..com/googleapis/java-shared-dependencies/commit/94a4e31634718a206ef0f5ff1a8801dc7be4c5c5))
---


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