deps: bump authlib from 1.5.1 to 1.6.4

Bumps [authlib](https://github.com/authlib/authlib) from 1.5.1 to 1.6.4.
- [Release notes](https://github.com/authlib/authlib/releases)
- [Changelog](https://github.com/authlib/authlib/blob/main/docs/changelog.rst)
- [Commits](authlib/authlib@v1.5.1...v1.6.4)

---
updated-dependencies:
- dependency-name: authlib
  dependency-version: 1.6.4
  dependency-type: indirect
...

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

Author: dependabot[bot]

requirements.txt

@@ -21,9 +21,9 @@ attrs==25.3.0 \
     # via
     #   jsonschema
     #   referencing
-authlib==1.5.1 \
-    --hash=sha256:5cbc85ecb0667312c1cdc2f9095680bb735883b123fb509fde1e65b1c5df972e \
-    --hash=sha256:8408861cbd9b4ea2ff759b00b6f02fd7d81ac5a56d0b2b22c08606c6049aae11
+authlib==1.6.4 \
+    --hash=sha256:104b0442a43061dc8bc23b133d1d06a2b0a9c2e3e33f34c4338929e816287649 \
+    --hash=sha256:39313d2a2caac3ecf6d8f95fbebdfd30ae6ea6ae6a6db794d976405fdd9aa796
     # via drf-oidc-auth
 cachetools==5.5.2 \
     --hash=sha256:1a661caa9175d26759571b2e19580f9d6393969e5dfca11fdb1f947a23e640d4 \