python: revision for gdbm

add regression test for gdbm module import

Fixes #22369.

Closes #22394.

Signed-off-by: ilovezfs <ilovezfs@icloud.com>

Formula/python.rb

@@ -3,6 +3,7 @@ class Python < Formula
   homepage "https://www.python.org/"
   url "https://www.python.org/ftp/python/2.7.14/Python-2.7.14.tar.xz"
   sha256 "71ffb26e09e78650e424929b2b457b9c912ac216576e6bd9e7d204ed03296a66"
+  revision 1
   head "https://github.com/python/cpython.git", :branch => "2.7"
 
   bottle do
@@ -374,6 +375,7 @@ class Python < Formula
     system "#{bin}/python2", "-c", "import sqlite3"
     # Check if some other modules import. Then the linked libs are working.
     system "#{bin}/python2", "-c", "import Tkinter; root = Tkinter.Tk()"
+    system "#{bin}/python2", "-c", "import gdbm"
     system bin/"pip2", "list"
   end
 end