fix: IntersectionType intersects more than 4 classes

[kpkonghk01]

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PR Type

Allow IntersectionType to accept any count of arguments, and join them together.

[x] Bugfix
[ ] Feature
[ ] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[ ] Build related changes
[ ] CI related changes
[ ] Other... Please describe:

What is the current behavior?

It doesn't accept more than 4 classes, blocked by the overloads.
And the return type of the original function is wrong, it only takes the first arg's type.

Also has a closed issue for this: #860

Does this PR introduce a breaking change?

[ ] Yes
[x] No

Other information

Fixing the problems in the discussion section of #341

Not sure if the helper types should be placed into a separate file since they only serve this function only

[kamilmysliwiec]

LGTM! Great PR