Utils: Increase tolerance of matrix vector product test

[RudolfWeeber]

to 8 epsilon

[codecov]

Codecov Report

Merging #3417 into python will not change coverage.
The diff coverage is n/a.

@@          Coverage Diff           @@
##           python   #3417   +/-   ##
======================================
  Coverage      86%     86%           
======================================
  Files         538     538           
  Lines       25282   25282           
======================================
  Hits        21805   21805           
  Misses       3477    3477

Impacted Files	Coverage Δ
src/utils/tests/matrix_vector_product.cpp	100% <ø> (ø)	⬆️

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[jngrad]

@junghans does this work for you?

[junghans]

Didn't help! see log

[jngrad]

Oh no, BOOST_CHECK_CLOSE takes a percentage value as the tolerance, epsilon must be multiplied by 100! I thought all those wrong unit tests had been corrected in 4.1, but visibly some of them survived.

[jngrad]

@fweik I'll take care of it in #3426

[jngrad]

Issue resolved by #3427