most template_method link targets do not link to the expected place

The automatic link target for `template_method` in docs targets the wrong place. It currently targets a tutorial instead of the template_method anchor on the files type promise page.

https://docs.cfengine.com/docs/master/reference-promise-types-files.html#template_method

So, `template_method` needs to be replaced with [template_method]files#template_method.