#265 Warn on redundant semicolon after else

[someoneigna]

Summary

Warn when a semicolon is found after else.

After this change a warning is reported for the semicolons at 7:7 12:15 and 16:2

let x = 0;
function f() {}
function g() {}

if (x) {
    f();
} else; {
    g();
}


if (x) {} else;
{ }

if (x) {} else
;{ }

Output in VIM plugin format is:

{"qflist": [{"col": 7, "lnum": 7, "end_col": 7, "end_lnum": 7, "type": "W", "nr": "E202", "vcol": 0, "text": "redundant semicolon after else", "filename": "invalid.js"},
{"col": 15, "lnum": 12, "end_col": 15, "end_lnum": 12, "type": "W", "nr": "E202", "vcol": 0, "text": "redundant semicolon after else", "filename": "invalid.js"},
{"col": 1, "lnum": 16, "end_col": 1, "end_lnum": 16, "type": "W", "nr": "E202", "vcol": 0, "text": "redundant semicolon after else", "filename": "invalid.js"}]}

else;;; {} is also valid code but was left out for simplicity. (loop of peek and skip required).

[github-actions[bot]]

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[someoneigna]

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[strager]

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