Pin back bundler version

Testing

.github/workflows/nightly.yml

@@ -6,7 +6,7 @@ on:
   workflow_dispatch:
 
 jobs:
-
+  
   spec:
     strategy:
       fail-fast: false
@@ -44,13 +44,17 @@ jobs:
           - puppet_gem_version: "~> 8.0"
             ruby_version: "3.2"
     name: "acceptance (ruby ${{ matrix.ruby_version }} | ${{ matrix.os }})"
+
     uses: "puppetlabs/cat-github-actions/.github/workflows/gem_acceptance.yml@main"
     secrets: "inherit"
     with:
       ruby_version: ${{ matrix.ruby_version }}
       puppet_version: ${{ matrix.puppet_gem_version }}
       rake_task: 'acceptance:local'
       runs_on: ${{ matrix.os }}
+      bundler-cache: false
+      BUNDLER_VERSION: "2.5.9"
+
 
   on-failure-workflow-restarter-proxy:
     # (1) run this job after the "acceptance" job and...