f13ad1cae0 modify test for memory locked in case locking pages failed at some point (Adam Jonas)
2fa85ebd1c add rpc_misc.py, mv test getmemoryinfo, add test mallocinfo (Adam Jonas)
Pull request description:
Creating the `rpc_misc.py` functional test file to add space for adding tests to a file that doesn't have a lot of coverage.
- Removing the `getmemoryinfo()` smoke test from wallet basic rather than moving it to keep the wallet decoupled. Feel like testing for reasonable memory allocation values should suffice.
- Adding coverage for `mallocinfo()`. Introduced standard lib XML parser since the function exports an XML string that describes the current state of the memory-allocation implementation in the caller.
Tree-SHA512: ced30115622916c88d1e729969ee331272ec9f2881eb36dee4bb7331bf633a6810a57fed63a0cfaf86de698edb5162e6a035efd07c89ece1df56b69d61288072
Backport of Core PR15485