Update Tiltfile: (#503)

## Description


This gets it working with the new build process.

Fixes: #

## How Has This Been Tested?





## How are existing users impacted? What migration steps/scripts do we need?





## Checklist:

I have:

- [ ] updated the documentation and/or roadmap (if required)
- [ ] added unit or e2e tests
- [ ] provided instructions on how to upgrade

Author: mergify[bot]

Tiltfile

@@ -1,7 +1,22 @@
+# Run `make build` to generate dist/artifacts.json and dist/metadata.json
+# before running this Tiltfile.
+artifacts = read_json('dist/artifacts.json')
+metadata = read_json('dist/metadata.json')
+
+goarch = metadata['runtime']['goarch']
+for x in artifacts:
+    if 'goarch' in x:
+        if x['goarch'] == goarch:
+            TARGETPLATFORM = "dist/build_{}".format(x['target'])
+            break
+
 docker_build(
     'ghcr.io/tinkerbell/cluster-api-provider-tinkerbell',
     '.',
     dockerfile='Dockerfile',
+    build_args={
+        'TARGETPLATFORM': TARGETPLATFORM,
+    },
 )
 k8s_yaml(kustomize('./config/default'))
 default_registry('ttl.sh/meohmy-dghentld')

config/default/manager_image_patch.yaml

@@ -8,5 +8,5 @@ spec:
     spec:
       containers:
       # Change the value of image field below to your controller image URL
-      - image: ghcr.io/tinkerbell/cluster-api-provider-tinkerbell:v0.6.6
+      - image: ghcr.io/tinkerbell/cluster-api-provider-tinkerbell:v0.6.7
         name: manager