Bump sexp_processor from 4.17.2 to 4.17.3

Bumps [sexp_processor](https://github.com/seattlerb/sexp_processor) from 4.17.2 to 4.17.3.
- [Changelog](https://github.com/seattlerb/sexp_processor/blob/master/History.rdoc)
- [Commits](seattlerb/sexp_processor@v4.17.2...v4.17.3)

---
updated-dependencies:
- dependency-name: sexp_processor
  dependency-type: indirect
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>

Gemfile.lock

@@ -117,7 +117,7 @@ GEM
       racc (~> 1.5)
       sexp_processor (~> 4.16)
     securerandom (0.3.2)
-    sexp_processor (4.17.2)
+    sexp_processor (4.17.3)
     simplecov (0.22.0)
       docile (~> 1.1)
       simplecov-html (~> 0.11)