different null validation messages for complex and primitive collections

[ElizabethOkerio]

Issues

This pull request fixes issue #1715.

Description

The error message returned by the null validation of a collection of primitive values and a collection of complex values is different. The expected result is for the error message for the null validation of both collections to be the same.

A null collection of primitive values returns this error message:

A null value was found for the property named 'XXX', 
which has the expected type 'Collection(Edm.String)[Nullable=False]'.
The expected type 'Collection(Edm.String)[Nullable=False]' 
does not allow null values.

while a null collections of complex values returns:

A node of type 'PrimitiveValue' was read from the JSON reader
when trying to read the contents of the property 'XXX';
however, a 'StartArray' node was expected

The expected result is for the error message for both collections to be:

A null value was found for the property named 'XXX', 
which has the expected type 'Collection(XXX)[Nullable=False]'. 
The expected type 'Collection(XXX)[Nullable=False]' does not allow null values

Checklist (Uncheck if it is not completed)

• Test cases added
• Build and test with one-click build and test script passed

Additional work necessary

If documentation update is needed, please add "Docs Needed" label to the issue and provide details about the required document change in the issue.

[g2mula]

Could you add a test to document/show this?

[paulodero]

Looks like some tests are failing.

[mikepizzo]

[KenitoInc]

LGTM

Already fixed