Revert "[rubygems/rubygems] Set thread configurations inside block"

This reverts commit db80e94.

This patch uses `Thread.abort_on_exception = true` and it affects
all of threads. This is why CI systems fails.

How to modify:

- use `thread.abort_on_exception = true` for specific threads
- Run this code in a separated process

lib/rubygems/gemcutter_utilities/webauthn_listener.rb

@@ -34,14 +34,14 @@ def initialize(host)
 
     def self.listener_thread(host, server)
       thread = Thread.new do
-        Thread.abort_on_exception = true
-        Thread.report_on_exception = false
         Thread.current[:otp] = new(host).wait_for_otp_code(server)
       rescue Gem::WebauthnVerificationError => e
         Thread.current[:error] = e
       ensure
         server.close
       end
+      thread.abort_on_exception = true
+      thread.report_on_exception = false
 
       thread
     end

lib/rubygems/gemcutter_utilities/webauthn_poller.rb

@@ -33,12 +33,12 @@ def initialize(options, host)
 
     def self.poll_thread(options, host, webauthn_url, credentials)
       thread = Thread.new do
-        Thread.abort_on_exception = true
-        Thread.report_on_exception = false
         Thread.current[:otp] = new(options, host).poll_for_otp(webauthn_url, credentials)
       rescue Gem::WebauthnVerificationError, Timeout::Error => e
         Thread.current[:error] = e
       end
+      thread.abort_on_exception = true
+      thread.report_on_exception = false
 
       thread
     end