ci: run ci also on forks (#160)

---------

Signed-off-by: Michele Dolfi <dol@zurich.ibm.com>
Signed-off-by: Michele Dolfi <97102151+dolfim-ibm@users.noreply.github.com>

.github/workflows/ci.yml

@@ -2,7 +2,7 @@ name: "Run CI"
 
 on:
   pull_request:
-    types: [opened, reopened]
+    types: [opened, reopened, synchronize]
   push:
     branches:
       - "**"
@@ -15,8 +15,10 @@ env:
 
 jobs:
   code-checks:
+    if: ${{ github.event_name == 'push' || (github.event.pull_request.head.repo.full_name != 'DS4SD/docling' && github.event.pull_request.head.repo.full_name != 'ds4sd/docling') }}
     uses: ./.github/workflows/checks.yml
   build-docs:
+    if: ${{ github.event_name == 'push' || (github.event.pull_request.head.repo.full_name != 'DS4SD/docling' && github.event.pull_request.head.repo.full_name != 'ds4sd/docling') }}
     uses: ./.github/workflows/docs.yml
     with:
       deploy: false