object-name: fix leaking symlink paths in object context

The object context may be populated with symlink contents when reading a
symlink, but the associated strbuf doesn't ever get released when
releasing the object context, causing a memory leak. Plug it.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

object-name.c

@@ -1765,6 +1765,7 @@ int strbuf_check_branch_ref(struct strbuf *sb, const char *name)
 void object_context_release(struct object_context *ctx)
 {
 	free(ctx->path);
+	strbuf_release(&ctx->symlink_path);
 }
 
 /*

t/t1006-cat-file.sh

@@ -2,6 +2,7 @@
 
 test_description='git cat-file'
 
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 
 test_cmdmode_usage () {