Fix too large dense matrix allocation issue

[geofjamg]

Please check if the PR fulfills these requirements

• The commit message follows our guidelines
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

Does this PR already have an issue describing the problem?

No

What kind of change does this PR introduce?

Bug fix

What is the current behavior?

When running a sensitivity analysis with too many contingencies we get the following exception:

Exception in thread "main" java.util.concurrent.CompletionException: java.lang.IndexOutOfBoundsException
	at java.base/java.util.concurrent.CompletableFuture.encodeThrowable(CompletableFuture.java:315)
	at java.base/java.util.concurrent.CompletableFuture.completeThrowable(CompletableFuture.java:320)
	at java.base/java.util.concurrent.CompletableFuture$AsyncRun.run(CompletableFuture.java:1807)
	at java.base/java.util.concurrent.CompletableFuture$AsyncRun.exec(CompletableFuture.java:1796)
	at java.base/java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:387)
	at java.base/java.util.concurrent.ForkJoinPool$WorkQueue.topLevelExec(ForkJoinPool.java:1311)
	at java.base/java.util.concurrent.ForkJoinPool.scan(ForkJoinPool.java:1841)
	at java.base/java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1806)
	at java.base/java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:177)
Caused by: java.lang.IndexOutOfBoundsException
	at java.base/java.nio.Buffer.checkIndex(Buffer.java:749)
	at java.base/java.nio.DirectByteBuffer.putDouble(DirectByteBuffer.java:1028)
	at com.powsybl.math.matrix.DenseMatrix.setUnsafe(DenseMatrix.java:123)
	at com.powsybl.math.matrix.DenseMatrix.set(DenseMatrix.java:129)
	at com.powsybl.openloadflow.sensi.DcSensitivityAnalysis.fillRhsContingency(DcSensitivityAnalysis.java:422)
	at com.powsybl.openloadflow.sensi.DcSensitivityAnalysis.initContingencyRhs(DcSensitivityAnalysis.java:429)
	at com.powsybl.openloadflow.sensi.DcSensitivityAnalysis.calculateContingenciesStates(DcSensitivityAnalysis.java:434)
	at com.powsybl.openloadflow.sensi.DcSensitivityAnalysis.analyse(DcSensitivityAnalysis.java:878)
	at com.powsybl.openloadflow.sensi.OpenSensitivityAnalysisProvider.lambda$run$0(OpenSensitivityAnalysisProvider.java:196)
	at java.base/java.util.concurrent.CompletableFuture$AsyncRun.run(CompletableFuture.java:1804)

This is because we try to allocate a too big dense matrix with a size >= max integer.

What is the new behavior (if this is a feature change)?
We throw a clear error message warning the user that there is too many contingencies defined.

Does this PR introduce a breaking change or deprecate an API?

• The Breaking Change or Deprecated label has been added
• The migration guide has been updated in the github wiki (What changes might users need to make in their application due to this PR?)

Other information:

[sonarcloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

100.0% Coverage
0.0% Duplication

[annetill]

I am okay with this message clarification but I wonder about the fact that we have a duplication of code here, no?

[geofjamg]

I am okay with this message clarification but I wonder about the fact that we have a duplication of code here, no?

Sonar do not report any duplication