Bump github.com/alecthomas/kong from 0.8.1 to 0.9.0 (closes #10)

Bumps [github.com/alecthomas/kong](https://github.com/alecthomas/kong) from 0.8.1 to 0.9.0.
- [Commits](https://github.com/alecthomas/kong/compare/v0.8.1...v0.9.0)

Change-Id: Ic4b810c6343a72c4027a7f22193fb0c588f9a65b

---
updated-dependencies:
- dependency-name: github.com/alecthomas/kong
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

Change-Id: I6621045e4166fd779ea86e5176c315bc6a323070
diff --git a/go.mod b/go.mod
index 69f4030..7bf3732 100644
--- a/go.mod
+++ b/go.mod
@@ -3,6 +3,6 @@
 go 1.16
 
 require (
-	github.com/alecthomas/kong v0.8.1
+	github.com/alecthomas/kong v0.9.0
 	github.com/stretchr/testify v1.9.0
 )