fix: remove TF registry URL + bump test GHA (#57)

## what

- Update TF Test GHA to the latest version that contains [critical fixes
for PR
checks](masterpointio/github-action-tf-test#12).
- Add required_version rule for .tf files without overriding
registryUrls.

## why

- On the previous GHA versions, TF tests were run on the default branch,
not the actual PR branch.
- The previous config incorrectly pointed Terraform core
required_version lookups to registry.terraform.io. Renovate fetches
Terraform core versions via GitHub releases (hashicorp/terraform), not
the registry API. This caused ERR_BODY_PARSE_FAILURE errors when the
registry returned HTML instead of JSON
([example](https://developer.mend.io/github/masterpointio/terraform-module-template/-/job/019afb59-7878-7f12-b243-45777c8bb870)).

Author: gberenice

.github/renovate.json5

@@ -1,7 +1,8 @@
+// Check Renovate logs: Go to https://developer.mend.io/ → sign in with GitHub → find your repo → check the job logs to see what Renovate is doing (or why it's skipping updates).
 {
   "extends": [
     "config:best-practices",
-    "github>aquaproj/aqua-renovate-config#2.7.5"
+    "github>aquaproj/aqua-renovate-config#2.9.0"
   ],
   "enabledManagers": [
     "terraform",
@@ -57,7 +58,6 @@
     {
       "matchFileNames": ["**/*.tf"],
       "matchDepTypes": ["required_version"],
-      "registryUrls": ["https://registry.terraform.io"],
       "groupName": "tf"
     }
   ]

.github/workflows/test.yaml

@@ -21,7 +21,7 @@ jobs:
       matrix:
         tf: [tofu, terraform]
     steps:
-      - uses: masterpointio/github-action-tf-test@c3b619f3bca9e4f482b9e0fb3166ab3f02d9d54c # v1.0.0
+      - uses: masterpointio/github-action-tf-test@c1e41998f67925ac3f34e0bbcfcaa4a44d1f0cd9 # v1.0.1
         with:
           tf_type: ${{ matrix.tf }}
           aws_role_arn: ${{ vars.TF_TEST_AWS_ROLE_ARN }}