Enable GHA workflow and update title/description

Author: mikesir87

.github/workflows/publish-labspace.yaml.temp renamed to .github/workflows/publish-labspace.yaml

@@ -1,7 +1,7 @@
 name: Package and deploy Labspace
 
 env:
-  DOCKERHUB_REPO: your-dockerhub-username/labspace-name
+  DOCKERHUB_REPO: dockersamples/labspace-testcontainers-java
 
 on:
   push:

labspace.yaml

@@ -1,6 +1,6 @@
-title: Labspace starter
+title: Testcontainers Java
 description: |
-  A basic template for creating a Labspace, including all of the boilerplate needed to write and publish a Labspace.
+  An introduction to using Testcontainers with a Java application.
 
 sections:
   - title: Getting Started