This commit makes sure to unwrap any transaction aware cache before
collecting metrics for them.

Closes gh-13861

Fixes gh-13636

This commit rework 1189ccc9 to prevent a mutate call on the original
headers map.

Closes gh-13871

Co-authored-by: Andy Bell <andyrbell@gmail.com>

Closes gh-13863

* pr/13871:
  Polish "Use Collection.removeIf() where possible"
  Use Collection.removeIf() where possible

Closes gh-13871

See gh-13871

* pr/13813:
  Polish "Add metric description and base unit to metrics endpoint"
  Add metric description and base unit to metrics endpoint

Closes gh-13813

See gh-13813

* pr/13819:
  Polish "Upgrade to Micrometer 1.0.6"
  Upgrade to Micrometer 1.0.6

Closes gh-13819

See gh-13819

Closes gh-13836

* gh-13818:
  Add null guards for getBeanDefinition() in BeanTypeRegistry

Closes gh-13818

Closes gh-13845

Closes gh-13844

Closes gh-13843

Closes gh-13842

Closes gh-13841

Closes gh-13840

Closes gh-13839

Closes gh-13838

Closes gh-13506

Closes gh-13505

Closes gh-13600

Closes gh-13827