Update build tag constraints

This patch updates all build tag constraints to add the new format,
alongside the old one, to maintain backwards compatibility.

This was done by using `go fmt`.

See https://go.dev/doc/go1.17#gofmt and
https://golang.org/design/draft-gobuild for more details.

cmd/chasquid-util/chasquid-util.go

@@ -1,6 +1,7 @@
 // chasquid-util is a command-line utility for chasquid-related operations.
 //
 // Don't include it in the coverage build.
+//go:build !coverage
 // +build !coverage
 
 package main