Merge changes from topic "ja/spm_rme"

* changes:
  refactor: cactus to handle expect exception
  test(memory share): memory contents checks
  refactor(spm): clean-up after failed memory share
  test(spm): lend/donate realm memory
  test(spm): use all constituents of memory share
  test(spm): validate GPC with memory sharing
  test(memory share): leverage rme for lend/donate