(fix): change ParameterId hashCode()

[mskangg]

Fixes #1901

• Objects.hash(pName, paramType, $ref) -> Objects.hash(pName);

In version 1.6.11 ParameterId was simply String name.
There is a new ParameterId in version 1.6.12 and there is a bug.
So I changed ParameterId.hashCode() code to String name.

[bnasslahsen]

@mskangg,

Thank you for your attempt!

For example, this use case is not handled:

	@GetMapping("/duplicate_param")
	@Operation(summary = "Duplicate param")
	@Parameter(name = "sample", required = true, in = ParameterIn.HEADER, description = "sample Header")
	@Parameter(name = "sample", required = true, in = ParameterIn.QUERY, description = "sample query")
	public String duplicateParam(@RequestParam String sample, @RequestHeader("sample") String sampleHeader) {
		return "duplicateParam";
	}