feat: TechDocs - Add vale linter to check words quality in md files. (#2631)

* fix(docs): typos which were reflacted from vale linter's command

* feat: Implement Vale linter (#2031)
Initialize .vale.ini file
Add 'lint:docs' script to package.json, to lint all md files except the ones which are located in node_modules
Generate 'vocab.txt' by using command 'yarn run lint:docs' | grep -o ''[a-z A-Z]*'' | grep -o '[a-z A-Z]*' | sort | uniq > .github/styles/vocab.txt
Add steps to github workflow 'master' to check docs quality

* chore: Separate workflow for quality checking

* chore: Added 'shx' dev dependency to support grep command in cross platform

* feat: Add script to operate same quality check process on different platform

* ignore: remove lint:docs from lint-stages which was added for experiment purpose

* fix: check-all-files on push event & check-changed-files on pull_request event

* chore(CI): triggle workflow only when there is any updates in .md file(s) on pull request

* fix: use spawnSync to solve 'The command line is too long.' error

* fix: github workflow syntax

* fix: prettier error

* chore: add vale command directly to lint-staged

* chore: use shebang for easy access

* fix: windows script issue & remove shebang

* chore: Add shebang flag

* chore: better error message related to vale

* chore: mention vale linter in documentation

* fix: spelling errors & add keywords to vocab.txt

docs/features/software-templates/extending/create-your-own-preparer.md

@@ -88,7 +88,7 @@ Some good examples exist here:
 - https://github.com/spotify/backstage/blob/master/plugins/scaffolder-backend/src/scaffolder/stages/prepare/file.ts
 - https://github.com/spotify/backstage/blob/master/plugins/scaffolder-backend/src/scaffolder/stages/prepare/github.ts
 
-### Registerinng your own Preparer
+### Registering your own Preparer
 
 You can register the preparer that you have created with the `PreparerBuilder`
 by using the `PreparerKey` from the Catalog, for example like this:

docs/features/techdocs/FAQ.md

@@ -35,4 +35,4 @@ well as a selection of Python Markdown extensions that TechDocs supports.
 Not right now. We are currently using MkDocs to generate the documentation from
 source, so the files have to be in Markdown format. However, in the future we
 want to support other static site generators which will make it possible to use
-otherfile formats.
+other file formats.