Enforce Go style rules across codebase

Apply five style rules: convert iota string enums to typed
string constants, replace errors.As with errors.AsType,
merge three-group imports into two groups, fix multiline
parameter/argument formatting, and replace fmt.Sprintf URL
construction with net/url.

Signed-off-by: Émile Ré <emile@probo.com>

pkg/certmanager/provisioner.go

@@ -21,13 +21,12 @@ import (
 	"strings"
 	"time"
 
+	"codeberg.org/miekg/dns"
 	"go.gearno.de/kit/log"
 	"go.gearno.de/kit/pg"
 	"go.probo.inc/probo/pkg/coredata"
 	"go.probo.inc/probo/pkg/crypto/cipher"
 	"go.probo.inc/probo/pkg/gid"
-
-	"codeberg.org/miekg/dns"
 )
 
 type (