extension_ci: Specify needed permissions for jobs (#45542)

GitHub flags these as security vulnerabilities. Hence, this PR specifies
the needed permissions for the workflows used in the `zed-extensions`
organization.

Release Notes:

- N/A

.github/workflows/extension_bump.yml

@@ -66,7 +66,7 @@ jobs:
     if: |-
       (github.repository_owner == 'zed-industries' || github.repository_owner == 'zed-extensions') &&
       (inputs.force-bump == 'true' || needs.check_bump_needed.outputs.needs_bump == 'true')
-    runs-on: namespace-profile-8x16-ubuntu-2204
+    runs-on: namespace-profile-2x4-ubuntu-2404
     steps:
     - id: generate-token
       name: extension_bump::generate_token
@@ -119,7 +119,7 @@ jobs:
     needs:
     - check_bump_needed
     if: (github.repository_owner == 'zed-industries' || github.repository_owner == 'zed-extensions') && github.event_name == 'push' && github.ref == 'refs/heads/main' && needs.check_bump_needed.outputs.needs_bump == 'false'
-    runs-on: namespace-profile-8x16-ubuntu-2204
+    runs-on: namespace-profile-2x4-ubuntu-2404
     steps:
     - id: generate-token
       name: extension_bump::generate_token

.github/workflows/extension_release.yml

@@ -13,7 +13,7 @@ on:
 jobs:
   create_release:
     if: (github.repository_owner == 'zed-industries' || github.repository_owner == 'zed-extensions')
-    runs-on: namespace-profile-8x16-ubuntu-2204
+    runs-on: namespace-profile-2x4-ubuntu-2404
     steps:
     - id: generate-token
       name: extension_bump::generate_token