ci: get rid of registries

.github/workflows/flakehub-publish-tagged.yml

@@ -1,16 +0,0 @@
-on:
-  push:
-    tags:
-      - "v*.*.*"
-jobs:
-  publish:
-    runs-on: "ubuntu-latest"
-    permissions:
-      id-token: "write"
-      contents: "read"
-    steps:
-      - uses: "actions/checkout@v3"
-      - uses: "DeterminateSystems/nix-installer-action@main"
-      - uses: "DeterminateSystems/flakehub-push@main"
-        with:
-          visibility: "public"

.github/workflows/flakestry.yaml

@@ -1,22 +0,0 @@
-name: "Publish a flake to flakestry"
-on:
-    push:
-        tags:
-        - "v?[0-9]+.[0-9]+.[0-9]+"
-        - "v?[0-9]+.[0-9]+"
-    workflow_dispatch:
-        inputs:
-            tag:
-                description: "The existing tag to publish"
-                type: "string"
-                required: true
-jobs:
-    publish-flake:
-        runs-on: ubuntu-latest
-        permissions:
-            id-token: "write"
-            contents: "read"
-        steps:
-            - uses: flakestry/flakestry-publish@main
-              with:
-                version: "${{ inputs.tag || github.ref_name }}"