(#13274) linters: Add annotations for YAML lint + add schema verification for config.yml and conandata.yml

* first attempt at a yaml linter wit github actions output

* This is less strict but has more information

* fixup message

* run config linter in Action

* better ux feedback

* try to use newlines

https://github.com/actions/toolkit/issues/193#issuecomment-605394935

* clean up

* fixup file name

* trying custom class for quoted str

* underlying yaml parser does not keep quotes

* trying to catch ints as problems

* remove test code

* and to "linter testing"

* install deps

* run new linter unconditionally

* revert testing changes

* new script for conandata (this one is much harder to spec)

* debugging

* lets see all the errors

* yamale -s ../linter/config_yaml_schema.yml aaf/config.yml

from linters folder as a test

* adjust script to match meeting discussion

* make sure the docs and linters match

* fix link

* Update conandata.yml

* exit 1 is not needed with annotations

* add annotation matchers for yaml since those do do much

* fix search for type

* fix whitespace

* tryout a yamllint file with a better looking matcher

* copy syntax from readme

* test if it's running in the wrong dir 🤔

* try with debug output

* bump since i dont have permissions

* bump - dont glob star

* bump

* less star globs

* also add action to conandata way

* bump

* drop action for cli + matcher

* more docs around linters

* fix file and name

* cleanup

docs/package_templates/msbuild_package/all/conandata.yml

@@ -1,16 +1,14 @@
 sources:
   # Newer versions at the top
   "1.2.0":
-    url: [
-      "https://mirror1.net/package-1.2.0.tar.gz",
-      "https://mirror2.net/package-1.2.0.tar.gz",
-    ]
+    url:
+    - "https://mirror1.net/package-1.2.0.tar.gz"
+    - "https://mirror2.net/package-1.2.0.tar.gz"
     sha256: "________________________________________________________________"
   "1.1.0":
-    url: [
-      "https://mirror1.net/package-1.1.0.tar.gz",
-      "https://mirror2.net/package-1.1.0.tar.gz",
-    ]
+    url:
+    - "https://mirror1.net/package-1.1.0.tar.gz"
+    - "https://mirror2.net/package-1.1.0.tar.gz"
     sha256: "________________________________________________________________"
 patches:
   # Newer versions at the top