change CI to **not** push to main when buildpdf fails

reason: buildpdf checks the commented code initialize example
we want this to pass before pushing to main otherwise that code
initializion example will be wrong

Author: lrvideckis

.github/workflows/programming_team_code_ci.yml

@@ -121,7 +121,7 @@ jobs:
 
   update_main:
     runs-on: ubuntu-latest
-    needs: [library_checker_aizu, grep_clangformat_cppcheck, clangtidy, compile_gcc, compile_clang, find_files_without_tests]
+    needs: [library_checker_aizu, grep_clangformat_cppcheck, clangtidy, compile_gcc, compile_clang, find_files_without_tests, build_pdf]
     if: github.ref == 'refs/heads/dev' && github.event_name == 'push'
     steps:
     - uses: actions/checkout@v4