Incorrect use of is function in PIR tests raises misleading error

[rfw]

When attempting to compare two non-Number values with the is function in a PIR test using an epsilon parameter, the following error occurs:

too many positional arguments: 4 passed, 4 expected

This message is misleading (not to mention that it makes no sense) and should be replaced with something more suitable.

[rfw]

Simple test case.

[nwellnhof]

Fixed in d4f23c7.

$ ./parrot lolwut.t
too many positional arguments: 4 passed, 3 expected
current instr.: 'parrot;Test;More;is' pc 122 (runtime/parrot/library/Test/More.pir:193)
called from Sub 'main' pc 32 (lolwut.t:5)