Have the `e2e.yml` workflows run only if `rust.yml` workflows pass

[srdtrk]

It seems that already we have too many runners to run them in parallel. It's also a waste to run e2e's if rust.yml is failing. We might also wanna add a job (in rust.yml) to see if testing contracts build. Since a common reason for e2e's to fail is forgetting to run cargo update on testing contracts

[srdtrk]

Reopening since the previous PR doesn't address the issue and is now reverted