SQLite3::ForkSafety.suppress_warnings!

Similar to this, which seems to not have been released for 7.2.x but has landed in main.

https://github.com/rails/rails/pull/53033/files#diff-13f18e985e903996e81f573b1fd364c19bddde279bc2797181491e6c146bcdc7R18

Author: JPrevost

test/test_helper.rb

@@ -54,14 +54,10 @@ class IntegrationTest
 
 module ActiveSupport
   class TestCase
+    SQLite3::ForkSafety.suppress_warnings!
+
     # Run tests in parallel with specified workers
-    # parallelize(workers: :number_of_processors)
-    # Setting to 1 manually to avoid sqlite fork warnings. Locally this seems to marginally
-    # increase total test time, but not enough that it seemed like a bad idea at this time.
-    # If our tests get slow, we can renable parallel tests and instead supress (or actually fix
-    # but it's unclear exactly how) the sqlite error.
-    # SQLite3::ForkSafety.suppress_warnings!
-    parallelize(workers: 1)
+    parallelize(workers: :number_of_processors)
 
     parallelize_setup do |worker|
       SimpleCov.command_name "#{SimpleCov.command_name}-#{worker}"