fix: sync VERSION to v1.1.5 (#34)

release-please-config.json was missing version-file before the
v1.1.5 release PR was generated, so VERSION was never updated.
Syncing manually so the file matches the current release.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: locus313

VERSION

@@ -1 +1 @@
-1.0.0
+1.1.5