cannot run the demo in README.md because of broken dependencies

[hitzhangjie]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. What did you do?
   If possible, provide a recipe for reproducing the error.

Run the demo in READEME.md

2. What did you expect to see?

Parse sql statement successfully and output the statement.

3. What did you see instead?

Build error because the module dependencies is broken.

[eqinox76]

Seems to be a duplicate of #812. It seems that one has to use a specific commit instead of the tag.
Example for getting v4.0.2:

go get github.com/pingcap/parser@3a18f1e5dceb2987570e6a1286d93c70f9af061f