Add Mega-Linter in list of integrations

[nvuillam]

Thanks for your nice linter, it works like a charm :)

yamllint page in Mega-Linter documentation is here -> https://nvuillam.github.io/mega-linter/descriptors/yaml_yamllint/

Please notify me if you have any remark :)

[coveralls]

Coverage remained the same at 97.92% when pulling 73308a3 on nvuillam:patch-1 into ee4d163 on adrienverge:master.

[adrienverge]

Hello Nicolas,

I'm glad to see that Mega-Linter uses yamllint!

However I'll close this PR because it does not bring any useful information to yamllint documentation (it should instead be documented in https://nvuillam.github.io/mega-linter/descriptors/yaml_yamllint/, which is already the case).

[nvuillam]

Usually linter docs have a section "tools integrating this linter", but your repo, your choice, have a nice day :)