fix var/const conflict, update format of test output, update json ignore

[JalonSolov]

Had to fix tests/5.struct.out due to recent changes in v fmt.

Fixed vlang/v#22116

[JalonSolov]

No idea why this is failing on macos... clang version, perhaps?

[spytheman]

I am checking on my m1 right now.

[spytheman]

It is reproducible locally.

[spytheman]

The getline functions is declared on the C side 🤔 :

0[16:20:54]@m1: (master) /opt/v $ rg getline /Applications/Xcode.app/Contents/Developer//Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/usr/include/stdio.h
358:ssize_t getline(char ** __restrict __linep, size_t * __restrict __linecapp, FILE * __restrict __stream) __OSX_AVAILABLE_STARTING(__MAC_10_7, __IPHONE_4_3);

[spytheman]

It is present in the clang's JSON output too:

      "isUsed": true,
      "name": "getline",
      "mangledName": "_getline",
      "type": {
        "qualType": "ssize_t (char **restrict, size_t *restrict, FILE *restrict)"
      },

[spytheman]

Afaik it is a regression from eafdd3c . For now, I've changed the .out file for macos to match the new output, so that the CI can pass :-| .