Bump diff-sequence package version to fix #10320. (#10331)

After @nathan-muir's PR #10053, we did not publish a new version of the
diff-sequence package, which would have contained DiffSequence.diffMaps.

I honestly have no idea why #10320 did not manifest before now, but
publishing these changes seems to fix it.

packages/diff-sequence/package.js

@@ -1,6 +1,6 @@
 Package.describe({
   summary: "An implementation of a diff algorithm on arrays and objects.",
-  version: '1.1.0',
+  version: '1.1.1',
   documentation: null
 });