Bump version for release.

NEWS

@@ -1,4 +1,4 @@
-1.9.7.dev0
+1.9.7
  * #855: Add a Sentry monitoring hook. See the documentation for more information:
    https://torsion.org/borgmatic/docs/how-to/monitor-your-backups/#sentry-hook
  * #968: Fix for a "spot" check error when a filename in the most recent archive contains a newline.

pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "borgmatic"
-version = "1.9.7.dev0"
+version = "1.9.7"
 authors = [
   { name="Dan Helfman", email="witten@torsion.org" },
 ]