ci/lava: Only check for the first section marker

Some LAVA signals have similar log outputs and the regex associated with
the log section may conflict. Use the policy of the first regex as the
chosen one, otherwise one line may produce two Gitlab sections in a row.

Signed-off-by: Guilherme Gallo <guilherme.gallo@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/22870>

.gitlab-ci/lava/utils/log_follower.py

@@ -124,6 +124,7 @@ class LogFollower:
         for log_section in LOG_SECTIONS:
             if new_section := log_section.from_log_line_to_section(line):
                 self.update_section(new_section)
+                break
 
     def detect_kernel_dump_line(self, line: dict[str, Union[str, list]]) -> bool:
         # line["msg"] can be a list[str] when there is a kernel dump