Restore support for Ruby 3.0 (#916)

Co-authored-by: Lin Jen-Shin <[email protected]>

Author: godfat

.github/workflows/ci.yml

@@ -30,7 +30,7 @@ jobs:
       GRAPE_VERSION: '1.7.1'
     strategy:
       matrix:
-        ruby-version: ['3.1', '3.2', '3.3', 'head']
+        ruby-version: ['3.0', '3.1', '3.2', '3.3', 'head']
     steps:
     - name: Check out branch
       uses: actions/checkout@v4
@@ -62,7 +62,7 @@ jobs:
       GRAPE_VERSION: '1.8.0'
     strategy:
       matrix:
-        ruby-version: ['3.1', '3.2', '3.3', 'head']
+        ruby-version: ['3.0', '3.1', '3.2', '3.3', 'head']
     steps:
     - name: Check out branch
       uses: actions/checkout@v4
@@ -94,7 +94,7 @@ jobs:
       GRAPE_VERSION: '2.0.0'
     strategy:
       matrix:
-        ruby-version: ['3.1', '3.2', '3.3', 'head']
+        ruby-version: ['3.0', '3.1', '3.2', '3.3', 'head']
     steps:
     - name: Check out branch
       uses: actions/checkout@v4
@@ -126,7 +126,7 @@ jobs:
       GRAPE_VERSION: 'HEAD'
     strategy:
       matrix:
-        ruby-version: ['3.1', '3.2', '3.3', 'head']
+        ruby-version: ['3.0', '3.1', '3.2', '3.3', 'head']
     steps:
     - name: Check out branch
       uses: actions/checkout@v4

grape-swagger.gemspec

@@ -14,7 +14,7 @@ Gem::Specification.new do |s|
 
   s.metadata['rubygems_mfa_required'] = 'true'
 
-  s.required_ruby_version = '>= 3.1'
+  s.required_ruby_version = '>= 3.0'
   s.add_runtime_dependency 'grape', '>= 1.7', '< 3.0'
   s.add_runtime_dependency 'rack-test', '~> 2'