fix(git): add vendor in .gitignore

vendor/github.com/gin-gonic/gin/binding/header.go

@@ -1,34 +0,0 @@
-package binding
-
-import (
-	"net/http"
-	"net/textproto"
-	"reflect"
-)
-
-type headerBinding struct{}
-
-func (headerBinding) Name() string {
-	return "header"
-}
-
-func (headerBinding) Bind(req *http.Request, obj interface{}) error {
-
-	if err := mapHeader(obj, req.Header); err != nil {
-		return err
-	}
-
-	return validate(obj)
-}
-
-func mapHeader(ptr interface{}, h map[string][]string) error {
-	return mappingByPtr(ptr, headerSource(h), "header")
-}
-
-type headerSource map[string][]string
-
-var _ setter = headerSource(nil)
-
-func (hs headerSource) TrySet(value reflect.Value, field reflect.StructField, tagValue string, opt setOptions) (isSetted bool, err error) {
-	return setByForm(value, field, hs, textproto.CanonicalMIMEHeaderKey(tagValue), opt)
-}