build(deps): bump requests from 2.27.1 to 2.31.0 in /.kokoro

Bumps [requests](https://github.com/psf/requests) from 2.27.1 to 2.31.0.
- [Release notes](https://github.com/psf/requests/releases)
- [Changelog](https://github.com/psf/requests/blob/main/HISTORY.md)
- [Commits](psf/requests@v2.27.1...v2.31.0)

---
updated-dependencies:
- dependency-name: requests
  dependency-type: indirect
...

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

.kokoro/requirements.txt

@@ -359,9 +359,9 @@ python-dateutil==2.8.2 \
     --hash=sha256:0123cacc1627ae19ddf3c27a5de5bd67ee4586fbdd6440d9748f8abb483d3e86 \
     --hash=sha256:961d03dc3453ebbc59dbdea9e4e11c5651520a876d0f4db161e8674aae935da9
     # via gcp-releasetool
-requests==2.27.1 \
-    --hash=sha256:68d7c56fd5a8999887728ef304a6d12edc7be74f1cfa47714fc8b414525c9a61 \
-    --hash=sha256:f22fa1e554c9ddfd16e6e41ac79759e17be9e492b3587efa038054674760e72d
+requests==2.31.0 \
+    --hash=sha256:58cd2187c01e70e6e26505bca751777aa9f2ee0b7f4300988b709f44e013003f \
+    --hash=sha256:942c5a758f98d790eaed1a29cb6eefc7ffb0d1cf7af05c3d2791656dbd6ad1e1
     # via
     #   gcp-releasetool
     #   google-api-core
@@ -374,10 +374,6 @@ secretstorage==3.3.3 \
     --hash=sha256:2403533ef369eca6d2ba81718576c5e0f564d5cca1b58f73a8b23e7d4eeebd77 \
     --hash=sha256:f356e6628222568e3af06f2eba8df495efa13b3b63081dafd4f7d9a7b7bc9f99
     # via keyring
-setuptools==67.3.2 \
-    --hash=sha256:95f00380ef2ffa41d9bba85d95b27689d923c93dfbafed4aecd7cf988a25e012 \
-    --hash=sha256:bb6d8e508de562768f2027902929f8523932fcd1fb784e6d573d2cafac995a48
-    # via -r requirements.in
 six==1.16.0 \
     --hash=sha256:1e61c37477a1626458e36f7b1d82aa5c9b094fa4802892072e49de9c60c4c926 \
     --hash=sha256:8abb2f1d86890a2dfb989f9a77cfcfd3e47c2a354b01111771326f8aa26e0254