Give up windows workflows

Author: azelcs

.github/workflows/build.yml

@@ -9,7 +9,6 @@ jobs:
       matrix:
         os:
           - ubuntu-22.04 # jammy
-          - windows-2022
         ruby:
           - '3.1'
           - '3.0'

spec/core_spec.rb

@@ -47,9 +47,7 @@
     end
 
     around(:each) do |example|
-      is_win = RUBY_PLATFORM =~ /mswin|mingw|cygwin/
-      executable = is_win ? 'opcua-server.exe' : 'opcua-server'
-      server_pid = spawn(File.join('tools', 'server', executable)) # Launch server
+      server_pid = spawn('tools/server/opcua-server') # Launch server
       example.run
       Process.kill('TERM', server_pid) # Stop server
     end