Git ignore .jetskicli files.

Mirror what Chromium did in https://crrev.com/c/7836304

Change-Id: I8e41ab87ed13df7e720ae9ac2285f886e6b29e8f
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/147691
Auto-Submit: Tom Sepez <tsepez@chromium.org>
Commit-Queue: Tom Sepez <tsepez@chromium.org>
Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>
diff --git a/.gitignore b/.gitignore
index 74c9a37..90b1329 100644
--- a/.gitignore
+++ b/.gitignore
@@ -58,6 +58,7 @@
 .gclient_entries
 .gdb_history
 .gdbinit
+.jetskicli
 *.aps
 *.filters
 *.opensdf