Update workflow to build Helm chart on main branch

This commit modifies the Git workflow for building the Helm chart
for Paperless NGX. The primary change is the update of the
triggering branch from 'patch-new-paperless' to 'main' for push
events. Additionally, the paths filter is re-enabled to ensure
that the workflow only triggers when changes are made to
"charts/paperless-ngx/Chart.yaml".

These adjustments were necessary to align the workflow with the
project's main branch, ensuring that any updates to the Helm
chart are promptly built and packaged. There are no breaking
changes in this update, but the workflow will not execute for
changes on other branches.

.gitea/workflows/build-chart-paperless-ngx.yml

@@ -2,9 +2,9 @@ name: "Build Helm Chart"
 on:
   push:
     branches:
-      - patch-new-paperless
+      - main
-    #paths:
+    paths:
-    #  - "charts/paperless-ngx/Chart.yaml"
+      - "charts/paperless-ngx/Chart.yaml"
 
 jobs:
   helm-package: