Bump int128/docker-manifest-create-action from 2.19.0 to 2.20.0

Bumps [int128/docker-manifest-create-action](https://github.com/int128/docker-manifest-create-action) from 2.19.0 to 2.20.0.
- [Release notes](https://github.com/int128/docker-manifest-create-action/releases)
- [Commits](https://github.com/int128/docker-manifest-create-action/compare/v2.19.0...v2.20.0)

---
updated-dependencies:
- dependency-name: int128/docker-manifest-create-action
  dependency-version: 2.20.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

.github/workflows/build-nightly-container.yml

@@ -86,7 +86,7 @@ jobs:
 
       # https://github.com/marketplace/actions/docker-manifest-create-action
       - name: Create and push manifest
-        uses: int128/docker-manifest-create-action@v2.19.0
+        uses: int128/docker-manifest-create-action@v2.20.0
         with:
           push: true
           tags: quay.io/invidious/invidious:master

.github/workflows/build-stable-container.yml

@@ -78,7 +78,7 @@ jobs:
 
       # https://github.com/marketplace/actions/docker-manifest-create-action
       - name: Create and push manifest
-        uses: int128/docker-manifest-create-action@v2.19.0
+        uses: int128/docker-manifest-create-action@v2.20.0
         with:
           push: true
           tags: quay.io/invidious/invidious:latest