remove tar.gz archives from goreleaser config (#465)

There is a known issue where adding tar.gz or other archives can
sometimes create a bad release because Terraform only supports zip.
hashicorp/terraform#26282

Author: pgier

.goreleaser.yaml

@@ -32,7 +32,7 @@ builds:
       goarch: '386'
   binary: '{{ .ProjectName }}_v{{ .Version }}'
 archives:
-- formats: ["zip", "tar.gz"]
+- formats: ["zip"]
   name_template: '{{ .ProjectName }}_{{ .Version }}_{{ .Os }}_{{ .Arch }}'
 checksum:
   name_template: '{{ .ProjectName }}_{{ .Version }}_SHA256SUMS'