new: [apache/log-rotate] can configure the rotation count from ``compose.yml``.

apache/hooks/log_rotate-relation-joined

@@ -14,6 +14,9 @@ LOGS=/var/log/apache2
 #     return 1
 # }
 
+rotated_count=$(relation-get rotated-count 2>/dev/null) || true
+rotated_count=${rotated_count:-52}
+
 ## XXXvlab: a lot of this intelligence should be moved away into ``logrotate`` charm
 DST="$CONFIGSTORE/$TARGET_SERVICE_NAME/etc/logrotate.d/$SERVICE_NAME"
 file_put "$DST" <<EOF
@@ -26,7 +29,7 @@ file_put "$DST" <<EOF
     dateyesterday
     dateformat _%Y-%m-%d
     extension .log
-    rotate 52
+    rotate $rotated_count
     compress
     delaycompress
     notifempty