[Form] remove MinCount and MaxCount constraints in ValidatorTypeGuesser

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | no
| License       | MIT
| Doc PR        | 

MinCount and MaxCount has been removed and replaced by Count (in 2.2 also).