[math] look at node in proper order

[ferdymercury]

This Pull request:

Changes or fixes:

This solution copies the same structure from lines 590 where the if-else statements are doing something different.

See

root/math/mathcore/src/TKDTree.cxx

Lines 575 to 581 in 65b3913

	if (point[fAxis[inode]]<fValue[inode]){
	//first examine the node that contains the point
	UpdateNearestNeighbors(GetLeft(inode), point, kNN, ind, dist);
	UpdateNearestNeighbors(GetRight(inode), point, kNN, ind, dist);
	} else {
	UpdateNearestNeighbors(GetRight(inode), point, kNN, ind, dist);
	UpdateNearestNeighbors(GetLeft(inode), point, kNN, ind, dist);

Fixes https://its.cern.ch/jira/browse/ROOT-10374

Checklist:

• tested changes locally
• updated the docs (if necessary)

[github-actions]

Test Results

    19 files      19 suites   4d 14h 9m 47s ⏱️
 2 731 tests  2 731 ✅ 0 💤 0 ❌
50 408 runs  50 408 ✅ 0 💤 0 ❌

Results for commit 943ba48.

[lmoneta]

It is probably correct, but can we have a simple test showing the problem existing before?
Also, why the condition is now from <= to < ?

[ferdymercury]

Thanks for the review

Also, why the condition is now from <= to < ?

To be consistent with the block starting at line 590.

It is probably correct, but can we have a simple test showing the problem existing before?

I think I do not know enough of this class to prepare a test, sorry :s