Ignore templated files

Avoid using file extensions from files under
templates/ folders as they are unlikely to validate
using their extension type. For example .yaml files
from these are likely jinja2 templated.

Fixes: #1511

.pre-commit-config.yaml

@@ -48,6 +48,7 @@ repos:
   - id: yamllint
     exclude: >
       (?x)^(
+        examples/playbooks/templates/.*|
         examples/other/some.j2.yaml
       )$
     files: \.(yaml|yml)$

examples/playbooks/templates/not-valid.yaml

@@ -0,0 +1,2 @@
+# Used to validate that a templated YAML file does not confuse the linter
+{% include 'port.j2' %}

src/ansiblelint/config.py

@@ -42,6 +42,7 @@
     # These assignations are only for internal use and are only inspired by
     # MIME/IANA model. Their purpose is to be able to process a file based on
     # it type, including generic processing of text files using the prefix.
+    {"text": "**/templates/**/*.*"},  # avoid being confused by extensions of templates
     {
         "text/jinja2": "**/*.j2"
     },  # jinja2 templates are not always parsable as something else