Update summarize-external-contribs to skip bot commits

Bot commits make the external contribution look smaller, since
it artificially inflates the "googler" count.

Bug: None
Change-Id: Iff547a4b818408f09b1b4ee1747c5631340d91d4
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/463001
Reviewed-by: Tomas Gunnarsson <tommi@webrtc.org>
Commit-Queue: Harald Alvestrand <hta@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#47410}

tools_webrtc/summarize_external_commits.py

diff --git a/tools_webrtc/summarize_external_commits.py b/tools_webrtc/summarize_external_commits.py
index 981f4ce..395a34b 100755
--- a/tools_webrtc/summarize_external_commits.py
+++ b/tools_webrtc/summarize_external_commits.py
@@ -64,6 +64,11 @@
         date_str = parts[1]
         month_key = date_str[:7]
 
+        # Exclude common bot/service account prefixes from all totals
+        if email.startswith('webrtc-version-updater') or email.startswith(
+                'chromium-webrtc-autoroll'):
+            continue
+
         # Track all commits per month (before filtering)
         monthly_all_summary[month_key] += 1
 
@@ -73,11 +78,6 @@
                for d in corporate_domains):
             continue
 
-        # Also exclude common bot/service account prefixes
-        if email.startswith('webrtc-version-updater') or email.startswith(
-                'chromium-webrtc-autoroll'):
-            continue
-
         # Update author counts
         author_counts[email] += 1
         domain_counts[domain] += 1