Bump ruby to 2.7.2, bump bundler 2.2.28 (#19488)

* Bump ruby to 2.7.2, bump bundler 2.2.28

* Bump in devcontainer variant as well

.devcontainer/devcontainer.json

@@ -4,7 +4,7 @@
     "dockerfile": "../Dockerfile",
     "context": "..",
     "args": {
-      "VARIANT": "2.6",
+      "VARIANT": "2.7",
       "NODE_VERSION": "12.1",
     }
   },

.github/workflows/test.yml

@@ -56,10 +56,10 @@ jobs:
     steps:
       - name: Check out files from GitHub
         uses: actions/checkout@v2.3.4
-      - name: Setting up Ruby 2.6
+      - name: Setting up Ruby 2.7
         uses: ruby/setup-ruby@v1.82.0
         with:
-          ruby-version: 2.6
+          ruby-version: 2.7
       - name: Setup Ruby Gems cache
         uses: actions/cache@v2.1.6
         with:
@@ -69,7 +69,7 @@ jobs:
             gems-
       - name: Installing dependencies
         run: |
-          gem install bundler -v 2.0.1
+          gem install bundler -v 2.2.28
           bundle config path vendor/bundle
           bundle install --jobs 4 --retry 3
       - name: Setting up Jekyll cache

.ruby-version

@@ -1 +1 @@
-2.6.2
+2.7.2

Gemfile.lock

@@ -143,4 +143,4 @@ RUBY VERSION
    ruby 2.6.2p47
 
 BUNDLED WITH
-   2.0.1
+   2.2.28