fix ruby syntax warnings

Closes Homebrew/homebrew#42409.

Signed-off-by: Xu Cheng <xucheng@me.com>

Library/Homebrew/test/test_download_strategies.rb

@@ -42,7 +42,7 @@ class VCSDownloadStrategyTests < Homebrew::TestCase
     strategy = Class.new(VCSDownloadStrategy) do
       def cache_tag
         "foo"
-                                     end
+      end
     end
     downloader = strategy.new("baz", resource)
     assert_equal HOMEBREW_CACHE.join("baz--foo"), downloader.cached_location

Library/Homebrew/test/test_formula_validation.rb

@@ -9,7 +9,7 @@ class FormulaValidationTests < Homebrew::TestCase
 
   def test_cant_override_brew
     e = assert_raises(RuntimeError) { formula { def brew; end } }
-    assert_match /You cannot override Formula#brew/, e.message
+    assert_match(/You cannot override Formula#brew/, e.message)
   end
 
   def test_validates_name

Library/Homebrew/test/test_patching.rb

@@ -83,7 +83,7 @@ class PatchingTests < Homebrew::TestCase
     assert_patched formula {
       def patches
         { :p0 => PATCH_URL_B }
-              end
+      end
     }
   end
 
@@ -91,7 +91,7 @@ class PatchingTests < Homebrew::TestCase
     assert_patched formula {
       def patches
         [PATCH_URL_A]
-              end
+      end
     }
   end
 
@@ -99,7 +99,7 @@ class PatchingTests < Homebrew::TestCase
     assert_patched formula {
       def patches
         { :p1 => PATCH_URL_A }
-              end
+      end
     }
   end
 
@@ -107,7 +107,7 @@ class PatchingTests < Homebrew::TestCase
     assert_patched formula {
       def patches
         { :p1 => [PATCH_URL_A] }
-              end
+      end
     }
   end