audit: version string should not be ambiguous with revision part

Closes Homebrew/homebrew#38810.

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

Library/Homebrew/cmd/audit.rb

@@ -847,6 +847,10 @@ class ResourceAuditor
     if version.to_s =~ /^v/
       problem "version #{version} should not have a leading 'v'"
     end
+
+    if version.to_s =~ /_\d+$/
+      problem "version #{version} should not end with a underline and a number"
+    end
   end
 
   def audit_checksum