Allow model generics in Table decorator

[KapitanOczywisty]

This PR helps when writing @Table definitions with hooks or other model-dependent options. I'm ignoring other decorators like @Column since these don't have any use from model.

I can use some help with updating docs, since I'm not a native speaker nor have any idea what I'm doing

@Table<Post>({
  hooks: {
    beforeUpdate: (instance) => {
      // this will result in error before PR
      instance.random = 4;
    },
  },
})
export class Post extends Model {
  @Column(DataType.INTEGER)
  random: number;
}

// alternative which works even now
@Table({
  hooks: {
    beforeUpdate: (instance: Post) => {
      // this works ok
      instance.random = 4;
    },
  },
})

[codecov]

Codecov Report

Merging #901 (b53c588) into master (3ba9667) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #901   +/-   ##
=======================================
  Coverage   95.20%   95.20%           
=======================================
  Files         117      117           
  Lines        1126     1126           
  Branches      129      129           
=======================================
  Hits         1072     1072           
  Misses         22       22           
  Partials       32       32           

Impacted Files	Coverage Δ
src/model/table/table.ts	100.00% <ø> (ø)

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