all: Format code with gofumpt

See https://github.com/mvdan/gofumpt

markup/tableofcontents/tableofcontents.go

@@ -131,8 +131,8 @@ func (b *tocBuilder) writeHeaders(level, indent int, h Headers) {
 		b.s.WriteString("\n")
 		b.indent(indent)
 	}
-
 }
+
 func (b *tocBuilder) writeHeader(level, indent int, h Header) {
 	b.indent(indent)
 	b.s.WriteString("<li>")

markup/tableofcontents/tableofcontents_test.go

@@ -152,5 +152,4 @@ func TestTocMissingParent(t *testing.T) {
     </li>
   </ol>
 </nav>`, qt.Commentf(got))
-
 }