roachtest: fix tenant auto upgrade scheduling user hooks during setup

The mixed version planner splits up a plan into two partitions,
setup steps and test steps. The latter will have user hooks
scheduled while the former will omit them.

The scheduling of user hooks is gated by the scheduleHooks boolean.
However, there was one edge case which omitted this check and
allowed for user hooks to be scheduled during version finalization
of a tenant.

Fixes: #145951
Release note: none

Author: DarrylWong

pkg/cmd/roachtest/roachtestutil/mixedversion/planner.go

@@ -938,10 +938,12 @@ func (p *testPlanner) finalizeUpgradeSteps(
 		// auto-upgrading after resetting a cluster setting, we need to
 		// "manually" run the migrations at this point.
 		if toVersion.AtLeast(tenantSupportsAutoUpgradeVersion) {
-			steps = append(
-				steps,
-				p.concurrently(mixedVersionLabel, p.hooks.MixedVersionSteps(p.currentContext, p.prng))...,
-			)
+			if scheduleHooks {
+				steps = append(
+					steps,
+					p.concurrently(mixedVersionLabel, p.hooks.MixedVersionSteps(p.currentContext, p.prng))...,
+				)
+			}
 		} else {
 			runStepsWithTenantMigrations()
 		}