ci: doc-build: bump timeout up to 45m

Give documentation a bit more time to build, seems like we are hitting
the current 30 minutes limit.

Signed-off-by: Fabio Baltieri <fabiobaltieri@google.com>

.github/workflows/doc-build.yml

@@ -36,7 +36,7 @@ jobs:
   doc-build-html:
     name: "Documentation Build (HTML)"
     runs-on: ubuntu-latest
-    timeout-minutes: 30
+    timeout-minutes: 45
     concurrency:
       group: doc-build-html-${{ github.ref }}
       cancel-in-progress: true
@@ -117,7 +117,7 @@ jobs:
     name: "Documentation Build (PDF)"
     runs-on: ubuntu-latest
     container: texlive/texlive:latest
-    timeout-minutes: 30
+    timeout-minutes: 45
     concurrency:
       group: doc-build-pdf-${{ github.ref }}
       cancel-in-progress: true