[Chapel Merge] updated the readme file for parser

Branch: refs/heads/master
Revision: 8e036a4
Author: bradcray
Log Message:

Merge pull request #17500 from vrockz747/parser_readme

updated the readme file for parser

[contributed by @vrockz747, reviewed by me]

Updated the readme file in chapel/compiler/parser.
Added more clarity to the steps telling how-to rebuild the compiler and removed trivial information - "in this
directory" to avoid confusion, as mentioned in issue #17467.

Modified Files:
M compiler/parser/README

Compare: https://github.com/chapel-lang/chapel/compare/251c4dcd786b...8e036a472beb