Meta: Hardcode lowercase repository name for devcontainer

This should unbreak CI.

.devcontainer/optimized/.devcontainer.json

@@ -1,11 +1,11 @@
 // The docker image used below was generated from '.devcontainer/devcontainer.json'
 // by the '.github/workflows/dev-container.yml' workflow.
 //
-// By building this dev container image in advance, tools 
-// like GitHub Codespaces (https://containers.dev/supporting) 
-// do not need to install all the prerequsite dependencies from scratch, 
+// By building this dev container image in advance, tools
+// like GitHub Codespaces (https://containers.dev/supporting)
+// do not need to install all the prerequsite dependencies from scratch,
 // getting you into your development environment faster!
 {
     "name": "SerenityOS (Pre-Built Image)",
-    "image": "ghcr.io/SerenityOS/serenity-devcontainer:base"
+    "image": "ghcr.io/serenityos/serenity-devcontainer:base"
 }

.github/workflows/dev-container.yml

@@ -1,6 +1,6 @@
 # This workflow builds a docker image with the Dev Container CLI (https://github.com/devcontainers/cli)
-# 
-name: 'Build Dev Container Image' 
+#
+name: 'Build Dev Container Image'
 on:
   workflow_dispatch:
   push:
@@ -9,7 +9,6 @@ on:
   schedule:
     # https://crontab.guru/#0_0_*_*_1
     - cron:  '0 0 * * 1'
-  
 
 permissions:
   contents: read
@@ -25,7 +24,7 @@ jobs:
         uses: actions/checkout@v3
 
       - name: Login to GitHub Container Registry
-        uses: docker/login-action@v2 
+        uses: docker/login-action@v2
         with:
           registry: ghcr.io
           username: ${{ github.repository_owner }}
@@ -34,6 +33,6 @@ jobs:
       - name: Build Base Dev Container Image
         uses: devcontainers/ci@v0.3
         with:
-          imageName: ghcr.io/${{ github.repository_owner }}/serenity-devcontainer
+          imageName: ghcr.io/serenityos/serenity-devcontainer
           imageTag: base,latest
           push: always