Fix embedded languages not displaying correctly

[nikitalita]

Description:

If you have embedded languages in the grammar you're providing, you need to provide an "embeddedLanguages" parameter in the "grammars" object with "<tm_id>": "<LANG>"; otherwise they won't display correctly in vscode.

Additionally, there were errors in the bounds-checking of embedded-language in the tmLanguage. If a subsequent recipe had any deps or params in the specifier, the end check would fail and the syntax coloring would bleed into the subsequent lins. I updated the tmLanguage to properly mark the "end" bound.

Finally, I updated the tests to correctly embed the embedded grammars in the snapshots. Please note: there were a bunch of tmLanguage files added in syntaxes/test-grammars to accomodate testing; this is only for testing, these are NOT used when the extension is running.

Testing/Screenshots:

Before:

After:

[nefrob]

This is awesome! Thanks for digging into this long standing setup issue. Snaps look good.

[nikitalita]

Done

[nefrob]

Released: https://github.com/nefrob/vscode-just/releases/tag/0.10.0.