Bump minimal ruby version require to 3.4.0

Author: biow0lf

.rubocop.yml

@@ -7,7 +7,7 @@ plugins:
   - rubocop-rspec
 
 AllCops:
-  TargetRubyVersion: 3.1
+  TargetRubyVersion: 3.4
   NewCops: enable
 
 # We use standard as a linter and formatter instead Rubocop.

.standard.yml

@@ -1 +1 @@
-ruby_version: 3.1
+ruby_version: 3.4

Gemfile.lock

@@ -218,4 +218,4 @@ CHECKSUMS
   uri (1.0.4) sha256=34485d137c079f8753a0ca1d883841a7ba2e5fae556e3c30c2aab0dde616344b
 
 BUNDLED WITH
-   2.6.8
+   4.0.4

errbit_github_plugin.gemspec

@@ -12,7 +12,7 @@ Gem::Specification.new do |spec|
   spec.description = "GitHub integration for Errbit"
   spec.homepage = "https://github.com/errbit/errbit_github_plugin"
   spec.license = "MIT"
-  spec.required_ruby_version = ">= 3.1.0"
+  spec.required_ruby_version = ">= 3.4.0"
 
   spec.metadata["homepage_uri"] = spec.homepage
   spec.metadata["source_code_uri"] = spec.homepage