CI Revamp by @crazy-max (#1873)

* CI revamped and other enhancements
GoReleaser for multi-arch binaries
Switch to GitHub Actions (more versatile) with 2 workflows
Docker multi-manifest image with buildx
Fix eslint run script
Go sum fixer
Use tools.go paradigm for external dependencies (packr)
Use go generate for packr

* Update workflows
* Add Slack notification
* Rebase
* Enhanced Dockerfile
* Fix go generate
* Fix Golangci lint
* Fix npm cache with v2 cache action
* Fix Dockerfile
* Trigger notif
* Issue with packr
* s390x platform not supported by packr
* Enhance layers
* Fix go modules

Co-authored-by: CrazyMax <crazy-max@users.noreply.github.com>

.dockerignore

@@ -0,0 +1,40 @@
+.DS_Store
+/.git
+/.github
+/.vscode
+.idea
+/AdGuardHome
+/AdGuardHome.exe
+/AdGuardHome.yaml
+/AdGuardHome.log
+/data
+/build
+/dist
+/client/node_modules
+/.gitattributes
+/.gitignore
+/.goreleaser.yml
+/changelog.config.js
+/coverage.txt
+/Dockerfile
+/LICENSE.txt
+/Makefile
+/querylog.json
+/querylog.json.1
+/*.md
+
+# Test output
+dnsfilter/tests/top-1m.csv
+dnsfilter/tests/dnsfilter.TestLotsOfRules*.pprof
+
+# Snapcraft build temporary files
+*.snap
+launchpad_credentials
+snapcraft_login
+snapcraft.yaml.bak
+
+# IntelliJ IDEA project files
+*.iml
+
+# Packr
+*-packr.go