Use canonical name for SHA1withECDSA

The Standard Names documentation says that "ECDSA" should not be used
due to its ambiguity. Bouncycastle has switched from "ECDSA" to
"SHA1withECDSA" so therefore we should switch this "workaround" Provider
to use the same name to keep it functioning correctly.

Bug: 27753949
Change-Id: I5acfca9d89c85bf005902a2f06cb5d7b1ef9dff2