fix(code-gen): fix empty where xxIn behaviour in the sql generator

[dirkdev98]

For some reason we skipped over empty xxIn arrays in the where generator. Now we handle the empty case correctly.

[github-actions]

==== Benchmark result ====

Node.js version: 14
Total benchmarks: 15
          Passed: 15
          Failed: 0
-----------
router - github static path              200000  iterations    7961  ns/op
router - github path params              200000  iterations   10053  ns/op
compas validator simple                 5000000  iterations     278  ns/op
yup validator simple                     100000  iterations   12063  ns/op
fastest-validator validator simple     10000000  iterations     121  ns/op
compas validator nested                 1000000  iterations    1485  ns/op
yup validator nested                      50000  iterations   37395  ns/op
fastest-validator validator nested      2000000  iterations     542  ns/op
logger - strings                         500000  iterations    2767  ns/op
logger - objects                         500000  iterations    3564  ns/op
logger - deep objects                    200000  iterations    6559  ns/op
uuid                                    2000000  iterations     553  ns/op
uuid.isValid                           10000000  iterations     180  ns/op
isNil                                 500000000  iterations       0  ns/op
isPlainObject                         100000000  iterations      20  ns/op

[github-actions]

==== C8 test coverage ====
Statements: 67.09% ( 27866/41537 )
Branches : 62.56% ( 2968 /4744 )
Functions : 69.22% ( 920 /1329 )
Lines : 67.09% ( 27866 /41537 )

[github-actions]

==== Benchmark result ====

Node.js version: 15
Total benchmarks: 15
          Passed: 15
          Failed: 0
-----------
router - github static path              200000  iterations    7633  ns/op
router - github path params              200000  iterations    8542  ns/op
compas validator simple                 5000000  iterations     219  ns/op
yup validator simple                     100000  iterations   10491  ns/op
fastest-validator validator simple     10000000  iterations     101  ns/op
compas validator nested                 1000000  iterations    1265  ns/op
yup validator nested                      50000  iterations   32950  ns/op
fastest-validator validator nested      5000000  iterations     470  ns/op
logger - strings                         500000  iterations    2340  ns/op
logger - objects                         500000  iterations    2876  ns/op
logger - deep objects                    500000  iterations    4108  ns/op
uuid                                    5000000  iterations     319  ns/op
uuid.isValid                           10000000  iterations     137  ns/op
isNil                                 500000000  iterations       0  ns/op
isPlainObject                         100000000  iterations      18  ns/op