Update rexer.gemspec

Author: hidakatsuya

rexer.gemspec

@@ -7,7 +7,7 @@ Gem::Specification.new do |spec|
   spec.email = ["hidakatsuya@gmail.com"]
 
   spec.summary = "A command-line tool for managing Redmine Plugins and Themes"
-  spec.description = "Rexer is a command-line tool for managing Redmine Extension (Plugin and Themes). It allows you to define extensions in a Ruby DSL and install, uninstall, update, and switch between different sets of the extensions."
+  spec.description = "Rexer is a command-line tool for managing Redmine Extensions (Plugins and Themes). It allows you to define extensions in a Ruby DSL and install, uninstall, update, and switch between different sets of the extensions."
   spec.homepage = "https://github.com/hidakatsuya/rexer"
   spec.license = "MIT"
   spec.required_ruby_version = ">= 3.1.0"