Rollup merge of #39530 - TimNN:more-gdb, r=alexcrichton

Rollup merge of #39530 - TimNN:more-gdb, r=alexcrichton

ignore more gdb versions with buggy rust support

This extends the versions of gdb which were ignored in #39039. While just ignoring gdb versions up to 7.12.1 would have been sufficient for now, I believe (after consulting https://sourceware.org/gdb/wiki/Internals%20Versions)  that ignoring versions up to 7.12.9 will prevent the tests failing again for 7.12.2, etc. while still running all tests for the development versions of gdb (which will be >= 7.12.10 as far as I can tell).

This should fix #39522.

cc @Manishearth, @michaelwoerister, #38948