CI: also capture stderr

.gitlab-ci.yml

@@ -4,7 +4,7 @@ buildjob:
   tags:
   - coq
   script:
-  - 'make -j8 TIMED=y | tee build-log.txt'
+  - 'make -j8 TIMED=y 2>&1 | tee build-log.txt'
   - 'cat build-log.txt  | egrep "[a-zA-Z0-9_/-]+ \(user: [0-9]" > build-time.txt'
   artifacts:
     paths: