Bump urllib3 from 1.26.16 to 1.26.18 in /.github/actions/merge

Bumps [urllib3](https://github.com/urllib3/urllib3) from 1.26.16 to 1.26.18.
- [Release notes](https://github.com/urllib3/urllib3/releases)
- [Changelog](https://github.com/urllib3/urllib3/blob/main/CHANGES.rst)
- [Commits](https://github.com/urllib3/urllib3/compare/1.26.16...1.26.18)

---
updated-dependencies:
- dependency-name: urllib3
  dependency-type: indirect
...

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

.github/actions/merge/requirements.txt

@@ -321,7 +321,9 @@ pygithub==1.59.0 \
 pyjwt[crypto]==2.7.0 \
     --hash=sha256:ba2b425b15ad5ef12f200dc67dd56af4e26de2331f965c5439994dad075876e1 \
     --hash=sha256:bd6ca4a3c4285c1a2d4349e5a035fdf8fb94e04ccd0fcbe6ba289dae9cc3e074
-    # via pygithub
+    # via
+    #   pygithub
+    #   pyjwt
 pynacl==1.5.0 \
     --hash=sha256:06b8f6fa7f5de8d5d2f7573fe8c863c051225a27b61e6860fd047b1775807858 \
     --hash=sha256:0c84947a22519e013607c9be43706dd42513f9e6ae5d39d3613ca1e142fba44d \
@@ -387,9 +389,9 @@ requests-toolbelt==0.10.1 \
     --hash=sha256:18565aa58116d9951ac39baa288d3adb5b3ff975c4f25eee78555d89e8f247f7 \
     --hash=sha256:62e09f7ff5ccbda92772a29f394a49c3ad6cb181d568b1337626b2abb628a63d
     # via gql
-urllib3==1.26.16 \
-    --hash=sha256:8d36afa7616d8ab714608411b4a3b13e58f463aee519024578e062e141dce20f \
-    --hash=sha256:8f135f6502756bde6b2a9b28989df5fbe87c9970cecaa69041edcce7f0589b14
+urllib3==1.26.18 \
+    --hash=sha256:34b97092d7e0a3a8cf7cd10e386f401b3737364026c45e622aa02903dffe0f07 \
+    --hash=sha256:f8ecc1bba5667413457c529ab955bf8c67b45db799d159066261719e328580a0
     # via
     #   gql
     #   requests