Use Schema constants for type values instead of string literals

[vearutop]

No description provided.

[codecov]

Codecov Report

Merging #22 into master will increase coverage by 0.28%.
The diff coverage is 87.5%.

@@             Coverage Diff              @@
##             master      #22      +/-   ##
============================================
+ Coverage     87.05%   87.33%   +0.28%     
- Complexity      458      459       +1     
============================================
  Files            37       37              
  Lines          1244     1248       +4     
============================================
+ Hits           1083     1090       +7     
+ Misses          161      158       -3

Impacted Files	Coverage Δ	Complexity Δ
src/PhpDoc.php	60.6% <ø> (-2.26%)	14 <0> (-1)
src/JsonSchema/SchemaBuilder.php	93.07% <87.5%> (+0.5%)	97 <0> (+2)	⬆️
src/JsonSchema/TypeBuilder.php	95.45% <0%> (+2.27%)	40% <0%> (ø)	⬇️

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