code-gen: remove validatorSetError

[dirkdev98]

This simplifies validator usage quite a bit.
When throwingValidators is true, AppError from @compas/stdlib is used.

[github-actions]

==== C8 test coverage ====
Statements: 69.06% ( 22703/32874 )
Branches : 68.14% ( 2537 /3723 )
Functions : 68.03% ( 779 /1145 )
Lines : 69.06% ( 22703 /32874 )

[github-actions]

==== Benchmark result ====

Node.js version: 15
Total benchmarks: 13
          Passed: 13
          Failed: 0
-----------
compas validator simple                 5000000  iterations      270  ns/op
yup validator simple                     100000  iterations    11536  ns/op
fastest-validator validator simple     10000000  iterations      115  ns/op
compas validator nested                   50000  iterations    47132  ns/op
yup validator nested                       5000  iterations   271830  ns/op
fastest-validator validator nested      2000000  iterations      919  ns/op
logger - strings                         500000  iterations     2288  ns/op
logger - objects                         500000  iterations     2864  ns/op
logger - deep objects                    500000  iterations     4571  ns/op
uuid                                    2000000  iterations      657  ns/op
uuid.isValid                           10000000  iterations      131  ns/op
isNil                                 500000000  iterations        0  ns/op
isPlainObject                         100000000  iterations       19  ns/op

[github-actions]

==== Benchmark result ====

Node.js version: 14
Total benchmarks: 13
          Passed: 13
          Failed: 0
-----------
compas validator simple                 5000000  iterations      316  ns/op
yup validator simple                     100000  iterations    12423  ns/op
fastest-validator validator simple     10000000  iterations      133  ns/op
compas validator nested                   50000  iterations    52088  ns/op
yup validator nested                       5000  iterations   287570  ns/op
fastest-validator validator nested      2000000  iterations      899  ns/op
logger - strings                         500000  iterations     2357  ns/op
logger - objects                         500000  iterations     2910  ns/op
logger - deep objects                    200000  iterations     5350  ns/op
uuid                                    2000000  iterations      549  ns/op
uuid.isValid                           10000000  iterations      129  ns/op
isNil                                 500000000  iterations        0  ns/op
isPlainObject                         100000000  iterations       17  ns/op