Improve content of notifications when the Usage Limit is reached

[jldec]

The current notification text does not provide enough guidance.

To fix:

• Follow the same detailed explanation as the workspace start error message which mentions the team
• Both should also link to your personal billing settings page where you can change billing accounts.

Existing notifications:

[jldec]

cc: @gtsiolis for design consideration 🙏 .

[svenefftinge]

I think it should mention the billing account and provide a link to switching to a different one (i.e. a link to the user's billing settings).
e.g. "The usage limit for 'team/user name' is almost reached. [Manage billing]."