build(deps): bump github.com/stretchr/testify from 1.4.0 to 1.5.1 (#120)

Bumps [github.com/stretchr/testify](https://github.com/stretchr/testify) from 1.4.0 to 1.5.1.
- [Release notes](https://github.com/stretchr/testify/releases)
- [Commits](https://github.com/stretchr/testify/compare/v1.4.0...v1.5.1)

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

Co-authored-by: dependabot-preview[bot] <27856297+dependabot-preview[bot]@users.noreply.github.com>

go.mod

@@ -11,7 +11,7 @@ require (
 	github.com/sebest/xff v0.0.0-20160910043805-6c115e0ffa35
 	github.com/shurcooL/sanitized_anchor_name v1.0.0 // indirect
 	github.com/snabb/sitemap v1.0.0
-	github.com/stretchr/testify v1.4.0
+	github.com/stretchr/testify v1.5.1
 	golang.org/x/oauth2 v0.0.0-20200107190931-bf48bf16ab8d
 	gopkg.in/yaml.v2 v2.2.8
 	within.website/ln v0.8.0

go.sum

@@ -102,6 +102,8 @@ github.com/stretchr/testify v1.3.0 h1:TivCn/peBQ7UY8ooIcPgZFpTNSz0Q2U6UrFlUfqbe0
 github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
 github.com/stretchr/testify v1.4.0 h1:2E4SXV/wtOkTonXsotYi4li6zVWxYlZuYNCXe9XRJyk=
 github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
+github.com/stretchr/testify v1.5.1 h1:nOGnQDM7FYENwehXlg/kFVnos3rEvtKTjRvOWSzb6H4=
+github.com/stretchr/testify v1.5.1/go.mod h1:5W2xD1RspED5o8YsWQXVCued0rvSQ+mT+I5cxcmMvtA=
 golang.org/x/crypto v0.0.0-20180904163835-0709b304e793/go.mod h1:6SG95UA2DQfeDnfUPMdvaQW0Q7yPrPDi9nlGo2tz2b4=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/net v0.0.0-20180724234803-3673e40ba225/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=