In your suite xml use group-by-instances=”true”
Sample, where TestClass1 and TestClass2 has the same content as yours
<suite thread-count="2" verbose="10" name="testSuite" parallel="tests">
<test verbose="2" name="MytestCase" group-by-instances="true">
<classes>
<class name="com.crazytests.dataproviderissue.TestClass1" />
<class name="com.crazytests.dataproviderissue.TestClass2" />
</classes>
</test>
</suite>
I get the output
testA1
testA2
testA3
testB1
testB2
testB3