cocci: remove dead rule from "the_repository.pending.cocci"

The "parse_commit_gently" macro went away in [1], so we don't need to
carry this for its migration.

1. ea3f7e5 (revision: use repository from rev_info when parsing
   commits, 2020-06-23)

Signed-off-by: Ævar Arnfjörð Bjarmason <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: avar

contrib/coccinelle/the_repository.pending.cocci

@@ -34,14 +34,6 @@ expression G;
 + repo_parse_commit_internal(the_repository,
   E, F, G)
 
-@@
-expression E;
-expression F;
-@@
-- parse_commit_gently(
-+ repo_parse_commit_gently(the_repository,
-  E, F)
-
 @@
 expression E;
 @@