Support versions of Raku where Any.Int does not die

An upcoming version of Raku will include a change that adds Int methods to more invocants. This means that code like Any.Int will no longer throw an exception.

$ raku-new --version
Welcome to Rakudo™ v2022.12-1205-gfb205b31a.
Implementing the Raku® Programming Language v6.d.
Built on MoarVM version 2022.12-17-g60a268958.
$ raku-new  -e 'dd try Any.Int'
Use of uninitialized value of type Any in numeric context
  in code  at -e line 1
0

but

$ raku-old --version
Welcome to Rakudo™ v2022.06.
Implementing the Raku® Programming Language v6.d.
Built on MoarVM version 2022.06.
$ raku-old -e 'dd try Any.Int'
Nil

When Game::Entities uses that value to check whether a given entity exists in a sparse set, the result is literally the opposite:

$ raku-new -e 'dd so try .[ 1; .[ 0; 1 ] ] with [ [], [], [] ]'
Use of uninitialized value of type Any in numeric context
  in block  at -e line 1
Bool::True
$ raku-old -e 'dd so try .[ 1; .[ 0; 1 ] ] with [ [], [], [] ]'
Bool::False

This commit changes the cases where we rely on this exception so that the code continues to work with versions of Raku that come before and after this release.

See https://github.com/rakudo/rakudo/issues/5201