Move gemfiles into spec

Signed-off-by: Shizuo Fujita <fujita@clear-code.com>

Author: Watson1978

.github/workflows/linux.yml

@@ -18,7 +18,7 @@ jobs:
           - activesupport
           - no-activesupport
     env:
-      BUNDLE_GEMFILE: gemfiles/${{ matrix.gemfile }}.gemfile
+      BUNDLE_GEMFILE: spec/gemfiles/${{ matrix.gemfile }}.gemfile
     name: Ruby ${{ matrix.ruby }} unit testing on ${{ matrix.os }} (${{ matrix.gemfile }})
     steps:
     - uses: actions/checkout@v4

.gitignore

@@ -1,5 +1,5 @@
 .bundle
-gemfiles/*.gemfile.lock
+spec/gemfiles/*.gemfile.lock
 Gemfile.lock
 pkg/*
 coverage/*