Created a simpler docker publish github action (#33)

* modified docker build and push command

* Modified docker build

* Correcter docker build

* made repository name lower case

* Corrected plugin folder name

* Added docker push command

---------

Co-authored-by: Martin-Belton-gov <martin.belton@digital.education.gov.uk>

.github/workflows/publish-ghcr.yml

@@ -22,8 +22,8 @@ jobs:
 
     - name: Download Grafana Plugin
       run: |
-        mkdir -p grafana-cost-plugin
-        cd grafana-cost-plugin
+        mkdir -p latest-cost-plugin
+        cd latest-cost-plugin
         wget "https://github.com/DFE-Digital/Grafana.Plugin.CostManagement/releases/download/main/dfe-azurecostbackend-datasource-1.0.7.zip"
         wget "https://grafana.com/api/plugins/blackcowmoo-googleanalytics-datasource/versions/0.2.3/download" -O blackcowmoo-googleanalytics-datasource-0.2.3.zip
         ls
@@ -43,8 +43,8 @@ jobs:
 
     - name: Build Docker Image
       run: |
-        docker build . "${{ env.REGISTRY }}/DFE-Digital/Grafana.Plugin.CostManagement-azurecost:latest"
-        docker push "${{ env.REGISTRY }}/DFE-Digital/Grafana.Plugin.CostManagement-azurecost:latest"
+        docker build . -t ghcr.io/dfe-digital/grafana-azurecostplugin-grafana:latest
+        docker push ghcr.io/dfe-digital/grafana-azurecostplugin-grafana:latest   
 
     env:
       DOCKER_BUILDKIT: 1