build(deps): bump github.com/mattn/go-isatty from 0.0.19 to 0.0.20

Bumps [github.com/mattn/go-isatty](https://github.com/mattn/go-isatty) from 0.0.19 to 0.0.20.
- [Commits](mattn/go-isatty@v0.0.19...v0.0.20)

---
updated-dependencies:
- dependency-name: github.com/mattn/go-isatty
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

go.mod

@@ -17,7 +17,7 @@ require (
 	github.com/gruntwork-io/terratest v0.46.0
 	github.com/jinzhu/copier v0.4.0
 	github.com/julienschmidt/httprouter v1.3.0
-	github.com/mattn/go-isatty v0.0.19
+	github.com/mattn/go-isatty v0.0.20
 	github.com/metal-stack/go-ipam v1.11.3
 	github.com/miekg/dns v1.1.50
 	github.com/mittwald/go-helm-client v0.12.3

go.sum

@@ -579,8 +579,8 @@ github.com/mattn/go-isatty v0.0.11/go.mod h1:PhnuNfih5lzO57/f3n+odYbM4JtupLOxQOA
 github.com/mattn/go-isatty v0.0.12/go.mod h1:cbi8OIDigv2wuxKPP5vlRcQ1OAZbq2CE4Kysco4FUpU=
 github.com/mattn/go-isatty v0.0.14/go.mod h1:7GGIvUiUoEMVVmxf/4nioHXj79iQHKdU27kJ6hsGG94=
 github.com/mattn/go-isatty v0.0.16/go.mod h1:kYGgaQfpe5nmfYZH+SKPsOc2e4SrIfOl2e/yFXSvRLM=
-github.com/mattn/go-isatty v0.0.19 h1:JITubQf0MOLdlGRuRq+jtsDlekdYPia9ZFsB8h/APPA=
-github.com/mattn/go-isatty v0.0.19/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
+github.com/mattn/go-isatty v0.0.20 h1:xfD0iDuEKnDkl03q4limB+vH+GxLEtL/jb4xVJSWWEY=
+github.com/mattn/go-isatty v0.0.20/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
 github.com/mattn/go-runewidth v0.0.13/go.mod h1:Jdepj2loyihRzMpdS35Xk/zdY8IAYHsh153qUoGf23w=
 github.com/mattn/go-runewidth v0.0.15 h1:UNAjwbU9l54TA3KzvqLGxwWjHmMgBUVhBiTjelZgg3U=
 github.com/mattn/go-runewidth v0.0.15/go.mod h1:Jdepj2loyihRzMpdS35Xk/zdY8IAYHsh153qUoGf23w=