Update bundler to 4.0.15 (#304)

* Update bundler to 4.0.15

* Remove Gemfile.lock if testing against head

.github/workflows/ruby.yml

@@ -22,11 +22,19 @@ jobs:
 
     steps:
     - uses: actions/checkout@v4
+    - name: Strip lockfile on Ruby Head to bypass mismatch bundler version
+      if: matrix.ruby-version == 'head'
+      run: |
+        echo "Removing Gemfile.lock"
+        rm -f Gemfile.lock
     - name: Set up Ruby
       uses: ruby/setup-ruby@v1
       with:
         ruby-version: ${{ matrix.ruby-version }}
-        bundler-cache: true # runs 'bundle install' and caches installed gems automatically
+        bundler-cache: ${{ matrix.ruby-version != 'head' }} # runs 'bundle install' and caches installed gems automatically
+    - name: Install dependencies for Ruby head
+      if: matrix.ruby-version == 'head'
+      run: bundle install
     - name: Install apt packages
       run: sudo apt update && sudo apt install -yy grep binutils-multiarch
     - name: Run tests

Gemfile.lock

@@ -79,4 +79,4 @@ DEPENDENCIES
   yard (~> 0.9)
 
 BUNDLED WITH
-   2.6.9
+  4.0.15