Add Ruby 3.1 and 3.2 and remove Ruby 2.6 from Ruby test matrix

.github/workflows/tests.yml

@@ -39,7 +39,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        ruby-version: [2.6, 2.7, '3.0']
+        ruby-version: [2.7, '3.0', 3.1, 3.2]
 
     steps:
       - uses: actions/checkout@master

.ruby-version

@@ -0,0 +1 @@
+3.2.0

Gemfile.lock

@@ -95,6 +95,7 @@ GEM
     marcel (1.0.2)
     method_source (1.0.0)
     mini_mime (1.1.2)
+    mini_portile2 (2.8.1)
     minitest (5.17.0)
     mocha (2.0.2)
       ruby2_keywords (>= 0.0.5)
@@ -108,9 +109,8 @@ GEM
     net-smtp (0.3.3)
       net-protocol
     nio4r (2.5.8)
-    nokogiri (1.13.10-x86_64-darwin)
-      racc (~> 1.4)
-    nokogiri (1.13.10-x86_64-linux)
+    nokogiri (1.13.10)
+      mini_portile2 (~> 2.8.0)
       racc (~> 1.4)
     parallel (1.22.1)
     parser (3.1.3.0)
@@ -178,8 +178,8 @@ GEM
       actionpack (>= 5.2)
       activesupport (>= 5.2)
       sprockets (>= 3.0.0)
-    sqlite3 (1.5.4-x86_64-darwin)
-    sqlite3 (1.5.4-x86_64-linux)
+    sqlite3 (1.5.4)
+      mini_portile2 (~> 2.8.0)
     standard (1.19.1)
       language_server-protocol (~> 3.17.0.2)
       rubocop (= 1.39.0)
@@ -198,6 +198,7 @@ GEM
     zeitwerk (2.6.6)
 
 PLATFORMS
+  x86_64-darwin-19
   x86_64-linux
 
 DEPENDENCIES
@@ -213,4 +214,4 @@ DEPENDENCIES
   standardrb
 
 BUNDLED WITH
-   2.4.1
+   2.3.24