Add SqlModes class with SQL modes constants

[MauricioFauth]

• Creates the PhpMyAdmin\SqlParser\SqlModes class with the Context::SQL_MODE_* constants.
• Deprecates the Context::SQL_MODE_* constants.

I'm not sure if this is a good thing since an SQL mode can be different depending on the context.

[codecov]

Codecov Report

Merging #369 (d22606b) into master (9cf3396) will increase coverage by 0.07%.
The diff coverage is 85.71%.

@@             Coverage Diff              @@
##             master     #369      +/-   ##
============================================
+ Coverage     95.41%   95.48%   +0.07%     
- Complexity     2059     2060       +1     
============================================
  Files            67       67              
  Lines          4410     4412       +2     
============================================
+ Hits           4208     4213       +5     
+ Misses          202      199       -3     

Impacted Files	Coverage Δ
src/Context.php	96.42% <85.71%> (+2.79%)	⬆️

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[williamdes]

I'm not sure if this is a good thing since an SQL mode can be different depending on the context.

I am not sure to understand

[MauricioFauth]

I'm not sure if this is a good thing since an SQL mode can be different depending on the context.

I am not sure to understand

Some MySQL/MariaDB's SQL modes differ depending on the version. This differences are not handled by sql-parser. I'm not sure if this is relevant or not to sql-parser.

[williamdes]

I'm not sure if this is a good thing since an SQL mode can be different depending on the context.

I am not sure to understand

Some MySQL/MariaDB's SQL modes differ depending on the version. This differences are not handled by sql-parser. I'm not sure if this is relevant or not to sql-parser.

Maybe relevant, but for now we just store and handle the declared modes so nothing more to do I think