TUN-3470: Replace in-house logger calls with zerolog

vendor/github.com/rs/zerolog/internal/json/base.go

@@ -0,0 +1,11 @@
+package json
+
+type Encoder struct{}
+
+// AppendKey appends a new key to the output JSON.
+func (e Encoder) AppendKey(dst []byte, key string) []byte {
+	if dst[len(dst)-1] != '{' {
+		dst = append(dst, ',')
+	}
+	return append(e.AppendString(dst, key), ':')
+}