[web] Don't show option to change password for SIWE accounts

Summary: Pretty straightforward, we just hide this setting for accounts that have signed in with Ethereum (based solely on accountHasPassword check).

Test Plan:
SIWE Account:

"Traditional" account:

Reviewers: ashoat, tomek

Reviewed By: ashoat

Differential Revision: https://phab.comm.dev/D6364