ci: not to push sources on `*-entrypoint` tag

Sources should be pushed to the repo on a release tag only,
an `*-entrypoint` tag is an auxiliary one.

NO_DOC=ci
NO_TEST=ci
NO_CHANGELOG=ci

(cherry picked from commit 45cc4930)

.github/workflows/source.yml

@@ -2,8 +2,8 @@ name: source
 
 on:
   push:
-    tags:
-      - '**'
+    tags-ignore:
+      - '**-entrypoint'
   workflow_dispatch:
 
 env: