feat: release tar.gz to prepare for krew

as krew requires released binaries compacted as tar.gz

Signed-off-by: Mario Constanti <github@constanti.de>

.goreleaser.yaml

@@ -16,6 +16,7 @@ builds:
 
 archives:
   - format: binary
+  - format: tar.gz
 
 checksum:
   name_template: "checksums.txt"