[BUG] Using a param __getattr__() breaks __setattr__()

[helehex]

Bug description

When you declare __getattr__[]() with a parametric key, then using __setattr__() for that same type will give:

error: invalid call to 'setattr': missing 1 required positional argument: 'key'

Steps to reproduce

@value
struct MyType:
    fn __getattr__[key: StringLiteral](self) -> Int:
        return 0
    
    fn __setattr__(inout self, key: StringLiteral, value: Int):
        pass


fn main():
    var t = MyType()
    t.a = 1

System information

Host Information
  ================

  Target Triple: x86_64-unknown-linux
  CPU: skylake
  CPU Features: adx, aes, avx, avx2, bmi, bmi2, clflushopt, cmov, crc32, cx16, cx8, f16c, fma, fsgsbase, fxsr, invpcid, lzcnt, mmx, movbe, pclmul, popcnt, prfchw, rdrnd, rdseed, sahf, sgx, sse, sse2, sse3, sse4.1, sse4.2, ssse3, x87, xsave, xsavec, xsaveopt, xsaves

mojo 2024.7.3108 (ca019713)

modular 0.8.0 (39a426b5)

[helehex]

Regardless of whether or not the __setattr__() is parametric.