Ignore .jit-stamp generated file (#149401)

Author: sobolevn

.gitignore

@@ -141,6 +141,7 @@ Tools/unicode/data/
 /cross-build*/
 /jit_stencils*.h
 /jit_unwind_info*.h
+.jit-stamp
 /platform
 /profile-clean-stamp
 /profile-run-stamp