Bump google-cloud-spanner from 3.12.1 to 3.13.0

Bumps [google-cloud-spanner](https://github.com/googleapis/python-spanner) from 3.12.1 to 3.13.0.
- [Release notes](https://github.com/googleapis/python-spanner/releases)
- [Changelog](https://github.com/googleapis/python-spanner/blob/main/CHANGELOG.md)
- [Commits](googleapis/python-spanner@v3.12.1...v3.13.0)

---
updated-dependencies:
- dependency-name: google-cloud-spanner
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

Pipfile

@@ -10,7 +10,7 @@ autopep8 = "*"
 pylint = "*"
 
 [packages]
-google-cloud-spanner = "~=3.12"
+google-cloud-spanner = "~=3.13"
 prompt-toolkit = "*"
 cli-helpers = "*"
 pygments = "*"