Reproducer format change?

I am manually parsing testcases to inject them into Go Fuzz tests.

So far I have been able to use `binary.BigEndian.Uint32(b)` to retrieve an input length and pass that number of bytes after the size, if it matches.

However the most recent testcase looks like this:

```
$ hexdump clusterfuzz-testcase-minimized-FuzzFSECompress-5543357962911744
0000000 20ff 1700 0408 0606 0a0a 0301 0a0a 0a0a
0000010 200a
0000012
```

A length of `0xff200017` doesn't make sense as a size. I was unable to find any information on how to parse the testcases properly. Can someone assist in this?

Start with the hexdump for clusterfuzz-testcase-minimized-FuzzFSECompress-5543357962911744 and the reported binary.BigEndian.Uint32(b) parsing approach. Determine the testcase format and document how its bytes should be interpreted so the input can be injected into Go Fuzz tests.

Written by the indexing model from the issue text.