meta: add mailmap entry for ratracegrad

There are two AUTHORS entries for ratracegrad. Use a mailmap entry to
consolidate them into a single entry.

PR-URL: #40291
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Zijian Liu <lxxyxzj@gmail.com>

.mailmap

@@ -190,6 +190,7 @@ James M Snell <jasnell@gmail.com>
 James Nimlos <james@nimlos.com>
 Jan Krems <jan.krems@gmail.com> <jan.krems@groupon.com>
 Jenna Vuong <jennavuong@gmail.com> <hello@jennavuong.com>
+Jennifer Bland <ratracegrad@gmail.com> <jennifer.bland@sbdinc.com>
 JeongHoon Byun <outsideris@gmail.com>
 Jered Schmidt <tr@nslator.jp>
 Jeremiah Senkpiel <fishrock123@rocketmail.com>

AUTHORS

@@ -2289,7 +2289,7 @@ Andreas Girgensohn <andreasg@fxpal.com>
 Caleb Sander <caleb.sander@gmail.com>
 Dzmitry_Prudnikau <dzmitriyprudnikov@gmail.com>
 Ian McKellar <ianloic@google.com>
-Jennifer Bland <jennifer.bland@sbdinc.com>
+Jennifer Bland <ratracegrad@gmail.com>
 Kyle Fuller <kyle@fuller.li>
 Yongsheng Zhang <zyszys98@gmail.com>
 Neeraj Laad <neeraj.laad@uk.ibm.com>
@@ -2320,7 +2320,6 @@ Alexander Mills <alex@oresoftware.com>
 Rodrigo Bruno <rfbpb@google.com>
 Lovingly <42682205+lovinglyy@users.noreply.github.com>
 Klaus Meinhardt <klaus.meinhardt1@gmail.com>
-Jennifer Bland <ratracegrad@gmail.com>
 Sintendo <bram.speeckaert@gmail.com>
 Nitish Sakhawalkar <nitsakh@icloud.com>
 André Cruz <andre@cabine.org>