Hi,

Thanks for the library and the great effort.

I need help with an issue:

When I set allowUnknownFlags to false, camel-case flags are reported as unknown flag. However, when I set allowUnknownFlags to true, both camel-cased and dash-cased flags populate the same camel case key (e.g. out-dir and outDir result with { flags: outDir: "xxx" }).

I expected when allowUnknownFlags is true, both types of flags are allowed, because dash cased flags are already converted to camel case in the result object.

Please see examples below:

allowUnknownFlags: false with camel-case flag

const flags = { outDir: { type: "string", desc: "Some desc." } };
const result = meow("some help",  { flags, allowUnknownFlags: false });
console.log(result.flags);

Command: $ cmd --outDir models
Result: Unknown flag --outDir
Expected: { outDir: "models" }

allowUnknownFlags: true

const flags = { outDir: { type: "string", desc: "Some desc." } };
const result = meow("some help",  { flags, allowUnknownFlags: true });
console.log(result.flags);

Command: $ cmd --outDir models
Result: { outDir: "models" }

Command: $ cmd --out-dir models
Result: { outDir: "models" }

Kind Regards,