Change property Schema::$typeMap to constant Schema::TYPE_MAP

[Tigrov]

The change reduces size of cache.

Q	A
Is bugfix?	❌
New feature?	❌
Breaks BC?	❌
Fixed issues	-

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (e3d9164) 98.42% compared to head (ed6f03e) 98.42%.

Additional details and impacted files

@@            Coverage Diff            @@
##             master     #282   +/-   ##
=========================================
  Coverage     98.42%   98.42%           
  Complexity      330      330           
=========================================
  Files            19       19           
  Lines          1016     1016           
=========================================
  Hits           1000     1000           
  Misses           16       16           

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[what-the-diff]

PR Summary

• Adjustment to the $typeMap variable
  Firstly, we converted the $typeMap variable from a normal property (which can be changed) to a constant. For non-technical people, this means that it is always the same, it never changes. This makes it more secure and predictable. We used the private const TYPE_MAP term which, without getting too techy, is just a safer way to keep this information.
• Update in the loadColumnSchema method usage
  Next, we've also made changes to something we call the loadColumnSchema method. Methods are kinds of procedures or functions within our program. In the loadColumnSchema method, we replaced the way $this->typeMap was used with self::TYPE_MAP. This makes the method more harmonized with the change we made above, ensuring things work consistently across the system.