Refactor: run archival tests in parallel with others (temporalio#7108)

## What changed?
<!-- Describe what has changed in this PR -->
Refactor: run archival tests in parallel with others.

## Why?
<!-- Tell your future self why have you made these changes -->
After previous archival test refactoring it is now possible to run them
in parallel.

## How did you test it?
<!-- How have you verified this change? Tested locally? Added a unit
test? Checked in staging env? -->
Run tests.

## Potential risks
<!-- Assuming the worst case, what can be broken when deploying this
change to production? -->
No risks.

## Documentation
<!-- Have you made sure this change doesn't falsify anything currently
stated in `docs/`? If significant
new behavior is added, have you described that in `docs/`? -->
No.

## Is hotfix candidate?
<!-- Is this PR a hotfix candidate or does it require a notification to
be sent to the broader community? (Yes/No) -->
No.

tests/archival_test.go

@@ -72,9 +72,8 @@ type (
 )
 
 func TestArchivalSuite(t *testing.T) {
-	// TODO: archival doesn't support parallel yet: t.Parallel()
-	s := new(ArchivalSuite)
-	suite.Run(t, s)
+	t.Parallel() // This suite can work in parallel as long as it is the only one that use testcore.WithArchivalEnabled() option.
+	suite.Run(t, new(ArchivalSuite))
 }
 
 func (s *ArchivalSuite) SetupSuite() {