[FEATURE] Avoid triggering the tests when there is a change in markdown files

[miguelgfierro]

Description

Expected behavior with the suggested feature

Other Comments

[miguelgfierro]

trigger:
  branches:
    include:
    - main
    - staging
  paths:
    exclude:
    - '*.md'

not working

[miguelgfierro]

with:

trigger:
  branches:
    include:
    - main
    - staging
  paths:
    exclude:
    - 'README.md'

and I modify a readme file that is not in the root, the builds are triggered:
https://dev.azure.com/best-practices/recommenders/_build/results?buildId=48403&view=results