Replace usage of InMemoryInstance with InMemoryAccumulo

[keith-turner]

InMemoryInstance extends the Accumulo Instance class which was deprecated and removed in Accumulo 3. In the in-memory-accumulo/accumulo4 branch InMemoryInstance was removed because the upstream class went away. When attempting to compile datawave against accumulo 4 many changes were needed because InMemoryInstance no longer existed. These changes can be seen in the datawave accumulo4 branch. In the accumulo4 branch some of these usages were automatically changed using find and sed, see the commit message on 375793c for details.

If the integration branch were updated to remove use of InMemoryInstance this would reduce diffs between the integration and the accumulo4 branches. To do this a subset of the changes in NationalSecurityAgency/datawave-in-memory-accumulo@67aa6d0 may need to be pulled into the in-memory-accumulo main branch, like some of the constructor related changes to InMemoryAccumulo may be useful.

[keith-turner]

Looking at the changes in accumulo4 since it branched off of integration there are 126 lines where InMemoryInstance was removed.

$ git diff 21288f6c393a4108d0adb134fb15baf7429f90b4 | grep InMemoryInstance | wc -l
126

[keith-turner]

This is related to #2443