Fix remaining wsl_v5 whitespace findings (refs #61)

Insert the blank line wsl_v5 requires above `defer` and `go`
statements that share no variables with the statement above them.
Applied mechanically via `make lint-fix`; the diff is 60 added blank
lines and nothing else.

internal/blobgen/compress.go

@@ -64,6 +64,7 @@ func CompressStream(
 	}
 
 	closed := false
+
 	defer func() {
 		if !closed {
 			_ = w.Close()