Add workflow to check licenses

[NyanKiyoshi]

This adds a workflow that checks our repository does not use non-BSD-3 compatible licenses.

The workflow reviews each pull requests against given rules, and sends a summary.

[github-actions]

Differences Found

✅ No packages or licenses were added.

Summary

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License Name	Package Count	Packages
0BSD	1	Packages tslib
MPL-2.0	1	Packages axe-core
Public Domain	1	Packages jsonify
Python-2.0	1	Packages argparse
CC-BY-4.0	2	Packages @saleor/macaw-ui caniuse-lite
CC0-1.0	2	Packages language-subtag-registry type-fest
<<missing>>	3	Packages busboy saleor-app-template streamsearch
BSD-3-Clause	12	Packages @humanwhocodes/object-schema @saleor/eslint-plugin-saleor-app abab asn1js esquery ieee754 immutable signedsource source-map source-map-js sprintf-js tough-cookie
BSD-2-Clause	15	Packages @typescript-eslint/parser @typescript-eslint/typescript-estree css-what damerau-levenshtein dotenv entities escodegen eslint-scope espree esprima esrecurse estraverse esutils uri-js webidl-conversions
Apache-2.0	21	Packages @ampproject/remapping @humanwhocodes/config-array @humanwhocodes/module-importer @opentelemetry/api @opentelemetry/semantic-conventions @swc/helpers aria-query axobject-query bser detect-libc doctrine eslint-visitor-keys fb-watchman human-signals json-to-pretty-yaml remedial retes rxjs typescript xml-name-validator And 1 more...
ISC	38	Packages @saleor/app-sdk ast-types-flow cli-width cliui electron-to-chromium eslint-import-resolver-typescript fastq flatted fs.realpath get-caller-file glob glob-parent graceful-fs inflight inherits isexe lru-cache minimatch mute-stream once And 18 more...
MIT	742	Packages @0no-co/graphql.web @aashutoshrathi/word-wrap @ardatan/relay-compiler @ardatan/sync-fetch @babel/code-frame @babel/compat-data @babel/core @babel/generator @babel/helper-annotate-as-pure @babel/helper-compilation-targets @babel/helper-create-class-features-plugin @babel/helper-environment-visitor @babel/helper-function-name @babel/helper-hoist-variables @babel/helper-member-expression-to-functions @babel/helper-module-imports @babel/helper-module-transforms @babel/helper-optimise-call-expression @babel/helper-plugin-utils @babel/helper-replace-supers And 722 more...