Remove pstore related unit tests from CTS

Pstore test cases should not belong to CTS.
The test cases should be a part of GTS if really required.

Test: manual
Bug: 66431569
Bug: 63969981
Bug: 63913130
Signed-off-by: Srinavasa Nagaraju <Srinavasa.Nagaraju@sony.com>
Signed-off-by: Yoshitaka Seto <yoshitaka.seto@sony.com>
Signed-off-by: Mark Salyzyn <salyzyn@google.com>
Tested-by: Srinavasa Nagaraju <Srinavasa.Nagaraju@sony.com>
Change-Id: Icd326403711ad268ce28a3863045fc9b2f211461