planner: fix error when select view_name.col_name from view_name(#14314)

[XuHuaiyu]

cherry-pick #14314

What problem does this PR solve?

Before this commit:

tidb> create table t(a int);
Query OK, 0 rows affected (0.01 sec)
tidb> create view v as select * from t;
Query OK, 0 rows affected (0.01 sec)
tidb> desc select v.a from v;
ERROR 1054 (42S22): Unknown column 'v.a' in 'field list'

What is changed and how it works?

We build a projection upon the underlying select when execute select from a view.
The output name of the built projection should be view_name.col_name instead of underlying_table_name.col_name.

Check List

Tests

• Unit test

Code changes

• Has exported function/method change

Side effects

N/A

Related changes

• Need to cherry-pick to the release branch
  release-3.0, release-3.1

Release note

Fix an error when executing SQL like select view_name.col_name from view_name.

[francis0407]

LGTM

[francis0407]

Do we need to change DBName?

[zz-jason]

@XuHuaiyu PTAL. BTW, we can merge this PR firstly. Changing the DBName in another PR if needed.

[XuHuaiyu]

Nice catch.
#15611

[zz-jason]

LGTM

[sre-bot]

Your auto merge job has been accepted, waiting for 15573

[sre-bot]

/run-all-tests