`RecogniseClassical(SL(2,q)).isSLContained` does not give `true`

Not sure if this is an active problem or not, but I remember talking about this with @danielrademacher:

```gap-repl
gap> RecogniseClassical(SL(2,37)).isSLContained;
"unknown"
gap> RecogniseClassical(SL(2,25)).isSLContained;
"unknown"
```
versus
```gap-repl
gap> RecogniseClassical(SL(3,37)).isSLContained;
true
gap> RecogniseClassical(SL(4,37)).isSLContained;
true
```

So this is at least odd.