[rubygems/rubygems] Remove unnecessary rubygems filters

Since the lowest supported version is now 3.4.1.

ruby/rubygems@d00e03c52e

Author: deivid-rodriguez

spec/bundler/install/gemfile/specific_platform_spec.rb

@@ -1432,7 +1432,7 @@
     end
   end
 
-  it "does not fail when a platform variant is incompatible with the current ruby and another equivalent platform specific variant is part of the resolution", rubygems: ">= 3.3.21" do
+  it "does not fail when a platform variant is incompatible with the current ruby and another equivalent platform specific variant is part of the resolution" do
     build_repo4 do
       build_gem "nokogiri", "1.15.5"
 
@@ -1578,7 +1578,7 @@
     end
   end
 
-  it "adds current musl platform, when there are also gnu variants", rubygems: ">= 3.3.21" do
+  it "adds current musl platform, when there are also gnu variants" do
     build_repo4 do
       build_gem "rcee_precompiled", "0.5.0" do |s|
         s.platform = "x86_64-linux-gnu"

spec/bundler/resolver/platform_spec.rb

@@ -387,7 +387,7 @@
       should_resolve_as %w[thin-1.2.7-x64-mingw-ucrt]
     end
 
-    it "finds universal-mingw gems on x64-mingw-ucrt", rubygems: ">= 3.3.18" do
+    it "finds universal-mingw gems on x64-mingw-ucrt" do
       platform "x64-mingw-ucrt"
       dep "win32-api"
       should_resolve_as %w[win32-api-1.5.1-universal-mingw32]