Add thousands-separators when formatting "seconds since epoch" (#11312)

Author: emilk

.gitignore

@@ -49,6 +49,9 @@ perf.data*
 
 **/dataset/
 
+# insta snapshot temp file:
+*.pending-snap
+
 # Screenshots from samples etc.
 screenshot*.png
 

crates/store/re_log_types/src/index/timestamp.rs

@@ -168,7 +168,7 @@ impl Timestamp {
             TimestampFormatKind::UnixEpoch => {
                 format!(
                     "{}{}",
-                    timestamp.as_second(),
+                    re_format::format_int(timestamp.as_second()),
                     format_fractional_nanos(timestamp.subsec_nanosecond())
                 )
             }