Update dependency on sqlite3 gem to >= 2.1.0.rc3

This version contains protections against sqlite's lack of fork
safety. We also suppress the warnings related to forking with open
writable connections, despite the lost memory per-connection.

For more context, see:
https://github.com/sparklemotion/sqlite3-ruby/blob/main/adr/2024-09-fork-safety.md

Gemfile

@@ -158,7 +158,7 @@ platforms :ruby, :windows do
   gem "nokogiri", ">= 1.8.1", "!= 1.11.0"
 
   # Active Record.
-  gem "sqlite3", ">= 2.0"
+  gem "sqlite3", ">= 2.1.0.rc3"
 
   group :db do
     gem "pg", "~> 1.3"

activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb

@@ -11,9 +11,12 @@
 require "active_record/connection_adapters/sqlite3/schema_dumper"
 require "active_record/connection_adapters/sqlite3/schema_statements"
 
-gem "sqlite3", ">= 2.0"
+gem "sqlite3", ">= 2.1.0.rc3"
 require "sqlite3"
 
+# Suppress the warning that SQLite3 issues when open writable connections are carried across fork()
+SQLite3::ForkSafety.suppress_warnings!
+
 module ActiveRecord
   module ConnectionAdapters # :nodoc:
     # = Active Record SQLite3 Adapter