Update to Go 1.13 in go.mod

bluekeyes · bluekeyes · commit 32887c7120ec · 2020-01-13T22:14:17.000-08:00
Tests now use errors.Is, a Go 1.13 feature.
diff --git a/go.mod b/go.mod
@@ -1,3 +1,3 @@
 module github.com/bluekeyes/go-gitdiff
 
-go 1.12
+go 1.13

Original file line number	Diff line number	Diff line change
`@@ -1,3 +1,3 @@`
`1`	`1`	`module github.com/bluekeyes/go-gitdiff`
`2`	`2`
`3`		`-go 1.12`
	`3`	`+go 1.13`