S3: fix TestSignedStreamingUploadInvalidSignature test (#7421)

* Added continue statements after all state transitions in the state machine to ensure immediate state processing

* simplify

* remove redundant continue clause

* ensure wrong signature

weed/s3api/chunked_reader_v4.go

@@ -369,7 +369,6 @@ func (cr *s3ChunkedReader) Read(buf []byte) (n int, err error) {
 			// If we're at the end of a chunk.
 			if cr.n == 0 {
 				cr.state = readChunkTrailer
-				continue
 			}
 		case verifyChunk:
 			// Check if we have credentials for signature verification