roachtest: cleanup multitenant-fairness tests

Also integrate prometheus, --skip-init.

Release note: None

pkg/cmd/roachtest/tests/BUILD.bazel

@@ -13,6 +13,7 @@ go_library(
         "admission_control_elastic_cdc.go",
         "admission_control_index_overload.go",
         "admission_control_multi_store_overload.go",
+        "admission_control_multitenant_fairness.go",
         "admission_control_snapshot_overload.go",
         "admission_control_tpcc_overload.go",
         "allocator.go",
@@ -92,7 +93,6 @@ go_library(
         "mixed_version_schemachange.go",
         "multitenant.go",
         "multitenant_distsql.go",
-        "multitenant_fairness.go",
         "multitenant_tpch.go",
         "multitenant_upgrade.go",
         "multitenant_utils.go",
@@ -210,7 +210,6 @@ go_library(
         "//pkg/ts/tspb",
         "//pkg/util",
         "//pkg/util/binfetcher",
-        "//pkg/util/buildutil",
         "//pkg/util/cancelchecker",
         "//pkg/util/contextutil",
         "//pkg/util/ctxgroup",

pkg/cmd/roachtest/tests/admission_control.go

@@ -31,12 +31,9 @@ func registerAdmission(r registry.Registry) {
 	registerElasticControlForBackups(r)
 	registerElasticControlForCDC(r)
 	registerMultiStoreOverload(r)
+	registerMultiTenantFairness(r)
 	registerSnapshotOverload(r)
 	registerTPCCOverload(r)
 	registerTPCCSevereOverload(r)
 	registerIndexOverload(r)
-
-	// TODO(irfansharif): Once registerMultiTenantFairness is unskipped and
-	// observed to be non-flaky for 3-ish months, transfer ownership to the AC
-	// group + re-home it here.
 }