Replace vendor_config.php constants with an array

[MauricioFauth]

Constants are hard to deal with, so this pull request replaces the constants in the libraries/vendor_config.php file with an array.

The constants have been moved to the libraries/constants.php file and can be removed later.

[codecov]

Codecov Report

Merging #17257 (1e542cd) into master (8fd8c35) will decrease coverage by 0.76%.
The diff coverage is 0.00%.

@@             Coverage Diff              @@
##             master   #17257      +/-   ##
============================================
- Coverage     48.31%   47.54%   -0.77%     
  Complexity    16677    16677              
============================================
  Files           579      580       +1     
  Lines         60091    59482     -609     
============================================
- Hits          29033    28282     -751     
- Misses        31058    31200     +142     

Flag	Coverage Δ
dbase-extension	47.42% <0.00%> (-0.07%)	⬇️
recode-extension	47.44% <0.00%> (-0.03%)	⬇️
unit-7.2-ubuntu-latest	47.43% <0.00%> (-0.60%)	⬇️
unit-7.3-ubuntu-latest	50.10% <0.00%> (-0.05%)	⬇️
unit-7.4-ubuntu-latest	50.19% <0.00%> (+0.10%)	⬆️
unit-8.0-ubuntu-latest	?

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Impacted Files	Coverage Δ
index.php	0.00% <0.00%> (ø)
js/messages.php	0.00% <0.00%> (ø)
libraries/classes/Command/SetVersionCommand.php	61.53% <ø> (ø)
libraries/constants.php	0.00% <0.00%> (ø)
libraries/vendor_config.php	0.00% <0.00%> (ø)
setup/lib/common.inc.php	0.00% <ø> (ø)
show_config_errors.php	0.00% <ø> (ø)
url.php	0.00% <ø> (ø)
libraries/classes/Config/Descriptions.php	4.49% <0.00%> (-45.03%)	⬇️
libraries/classes/Charsets.php	52.00% <0.00%> (-30.70%)	⬇️
... and 133 more

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