expand econ-gov synpress tests to include invitation workflow

[rabi-siddique]

We will create a Synpress UI test that includes the following steps:

• Accepting invitations to join both the charter and committee. We need to ensure the user successfully accepts invitations for both.
• After the invitations are accepted, the new EC member should propose questions, potentially attempting to modify Vault parameters."

These tests will be separate from the usual econ-gov tests and will be run against A3P.