Update api version to 56.0 and test classes to use new Assert class

[chazwatkins]

This change is 

[ImJohnMDaniel]

G'day @chazwatkins -- Just wanted to say again thank you very much for this PR. There is a lot that you updated and it is very much appreciated. Cheers!

[ImJohnMDaniel]

G'day @chazwatkins. I noticed that fflib_SObjectDomain.TestSObjectStatefulDomain and fflib_SObjectDomain.TestSObjectDomain each have an assertion in the old style. Was this deliberate?

[ImJohnMDaniel]

Also, @chazwatkins, will you be updating the class xml files to v56.0? If not, no worries. I can definitely do it. I just didn't want to double up on the work.

Thanks again!!

[chazwatkins]

Since I was updating all the repos, I managed to forget to do the xml files on this one. I'll do this now.

[chazwatkins]

The xml files are now all 56.0

[chazwatkins]

G'day @chazwatkins. I noticed that fflib_SObjectDomain.TestSObjectStatefulDomain and fflib_SObjectDomain.TestSObjectDomain each have an assertion in the old style. Was this deliberate?

@ImJohnMDaniel It wasn't. I'll check on them and submit the update

[chazwatkins]

G'day @chazwatkins. I noticed that fflib_SObjectDomain.TestSObjectStatefulDomain and fflib_SObjectDomain.TestSObjectDomain each have an assertion in the old style. Was this deliberate?

@ImJohnMDaniel It wasn't. I'll check on them and submit the update

fflib_SObjectDomain.TestSObjectStatefulDomain and fflib_SObjectDomain.TestSObjectDomain are updated to use System.Assert.areEqual now

[stohn777]

Reviewable status: 0 of 40 files reviewed, 1 unresolved discussion (waiting on @chazwatkins and @daveespo)

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sfdx-source/apex-common/test/classes/fflib_SObjectDescribeTest.cls line 49 at r3 (raw file):

		System.Assert.isNull(fflib_SObjectDescribe.getDescribe(nullType));
		System.Assert.isNull(fflib_SObjectDescribe.getDescribe(nullDescribe));
		System.Assert.isNull(fflib_SObjectDescribe.getDescribe(nullSObject));

Should all of these use the Assert.areEqual(null, ...) pattern too? I cannot see how they would ever be insufficient, BUT ...

[chazwatkins]

Reviewable status: 0 of 40 files reviewed, 1 unresolved discussion (waiting on @chazwatkins and @daveespo)

sfdx-source/apex-common/test/classes/fflib_SObjectDescribeTest.cls line 49 at r3 (raw file):

		System.Assert.isNull(fflib_SObjectDescribe.getDescribe(nullType));
		System.Assert.isNull(fflib_SObjectDescribe.getDescribe(nullDescribe));
		System.Assert.isNull(fflib_SObjectDescribe.getDescribe(nullSObject));

Should all of these use the Assert.areEqual(null, ...) pattern too? I cannot see how they would ever be insufficient, BUT ...

Yes, they should be. Thanks for catching that. I double-checked for other isNull and isNotNull occurrences and updated them to areEqual(null, ...) and areNotEqual(null, ...)