Inconsistent span labeling

[jbouwman]

Several test cases exhibit inconsistent labeling of zero-length error spans, for instance the following, which labels the error as 4:15, while the note points to column 14.

https://github.com/coalton-lang/coalton/blob/67262cc3c1863ccd3b6d12eb296f001a4fa7a7f6/tests/parser-test-files/bad-files/parse-let.1.error#L4,L5

See also

define-class.16.error
define-instance.7.error
parse-and.1.error
parse-attribute.5.error
parse-body.1.error
parse-cond.1.error
parse-cond.4.error
parse-do.4.error
parse-fn.1.error
parse-fn.2.error
parse-for.1.error
parse-for.2.error
parse-for.3.error
parse-for.4.error
parse-for.5.error
parse-if.1.error
parse-if.2.error
parse-if.3.error
parse-if.4.error
parse-let.2.error
parse-let.5.error
parse-lisp.1.error
parse-lisp.2.error
parse-loop.1.error
parse-loop.2.error
parse-match.1.error
parse-match.2.error
parse-or.1.error
parse-the.1.error
parse-the.2.error
parse-unless.1.error
parse-unless.2.error
parse-when.1.error
parse-when.2.error
parse-while-let.1.error
parse-while-let.2.error
parse-while-let.3.error
parse-while-let.4.error
parse-while-let.5.error
parse-while-let.6.error
parse-while-let.7.error
parse-while-let.8.error
parse-while-let.9.error
parse-while.1.error
parse-while.2.error
parse-while.3.error
parse-while.4.error