Fix -Wrange-loop-construct warning

Fixing these warnings either by adding a reference to the loop index's
type or removing the reference from it.

frameworks/av/media/libaudiohal/tests/EffectsFactoryHalInterface_test.cpp
:381:25: error: loop variable 'combination' creates a copy from type
'std::shared_ptr<android::EffectParamCombination> const'
[-Werror,-Wrange-loop-construct]
  381 |         for (const auto combination : mCombinations) {
      |                         ^
frameworks/av/media/libaudiohal/tests/EffectsFactoryHalInterface_test.cpp
:381:14: note: use reference type
'std::shared_ptr<android::EffectParamCombination> const &' to prevent
copying
  381 |         for (const auto combination : mCombinations) {
      |              ^~~~~~~~~~~~~~~~~~~~~~~~

Bug: 153747076
Test: m & presubmits
Flag: EXEMPT refactor
Change-Id: I1ac63c321e7bc19a4d72cf9072146fab8d3eafb9