Add change tracker entry

Author: Kobzol

src/bootstrap/src/utils/change_tracker.rs

@@ -365,4 +365,9 @@ pub const CONFIG_CHANGE_HISTORY: &[ChangeInfo] = &[
         severity: ChangeSeverity::Info,
         summary: "`rust.channel` now supports \"auto-detect\" to load the channel from `src/ci/channel`",
     },
+    ChangeInfo {
+        change_id: 0,
+        severity: ChangeSeverity::Info,
+        summary: "There is now a new `gcc` config section that can be used to download GCC from CI using `gcc.download-ci-gcc = true`",
+    },
 ];