chore(ci): add automatic link checking for markdown

bin/check-docs

@@ -0,0 +1,6 @@
+#!/bin/bash -e
+
+# linter before git check so we can lint docs even if they are 'dirty'
+find docs -name '*.md' -type f -exec markdown-link-check  {} \;
+
+git diff --quiet HEAD -- docs/ || (echo 'generated docs are not up-to-date!' && exit 1)

docs/reference/glossary.md

@@ -5,7 +5,7 @@ Represents the current configuration and status of any running services in the [
 inspected and modified via the Garden CLI's `environment` command.
 
 Several named environment configurations may be defined (e.g. _dev_, _testing_, ...) in the [project's
-`garden.yml`](../guides/configuration.md#project-configuration).
+`garden.yml`](../using-garden/configuration-files.md#project-configuration).
 
 #### Module
 The basic unit of configuration in Garden. A module is defined by its

package.json

@@ -30,6 +30,7 @@
     "husky": "^0.15.0-rc.13",
     "lerna": "^3.0.4",
     "lodash": "^4.17.11",
+    "markdown-link-check": "^3.7.2",
     "shx": "^0.3.2",
     "snyk": "^1.90.2",
     "ts-node": "^7.0.1",
@@ -41,7 +42,7 @@
   },
   "scripts": {
     "build": "npm run clean && gulp build",
-    "check-docs": "git diff --quiet HEAD -- docs/ || (echo 'generated docs are not up-to-date!' && exit 1)",
+    "check-docs": "./bin/check-docs",
     "check-licenses": "gulp check-licenses",
     "check-package-lock": "git diff --quiet HEAD -- package-lock.json || (echo 'package-lock.json is dirty!' && exit 1)",
     "clean": "lerna run clean && git clean -X -f",