build(deps): pin fedora docker tag to 781b764

Signed-off-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

.github/workflows/test-fedora-install.yml

@@ -14,7 +14,7 @@ jobs:
     runs-on: ubuntu-latest
     name: Test on Fedora 43
     container:
-      image: fedora:43 # renovate: datasource=docker depName=fedora
+      image: fedora:43@sha256:781b7642e8bf256e9cf75d2aa58d86f5cc695fd2df113517614e181a5eee9138 # renovate: datasource=docker depName=fedora
       options: --user root
     steps:
       - name: Install prerequisites

.github/workflows/test-unit-fedora.yml

@@ -29,7 +29,7 @@ jobs:
   test-fedora:
     runs-on: ubuntu-24.04
     container:
-      image: fedora:43 # renovate: datasource=docker depName=fedora
+      image: fedora:43@sha256:781b7642e8bf256e9cf75d2aa58d86f5cc695fd2df113517614e181a5eee9138 # renovate: datasource=docker depName=fedora
     steps:
       - name: Install prerequisites
         run: |