[KeyVault] - Bump Keys timeout to 90 minutes (#15489)

KeyVault Keys tests have been timing out on Managed HSM. Looking at the runs, it does look like we are just on the edge of timing out but a few recent test additions have put us over the edge.

There are N Key Vault tests + M Managed HSM specific tests, so only the Managed HSM runs started timing out. I think bumping to 90 minutes is a reasonable strategy here as I didn't see any large changes in the trends.

sdk/keyvault/keyvault-keys/tests.yml

@@ -5,7 +5,7 @@ stages:
     parameters:
       PackageName: "@azure/keyvault-keys"
       ServiceDirectory: keyvault
-      TimeoutInMinutes: 59
+      TimeoutInMinutes: 90
       # KV HSM limitation prevents us from running live tests
       # against multiple platforms in parallel (we're limited to a single
       # instance per region per subscription) so we're only running