Previously generators could generate code from inputs that didn't exist and get back the empty string. This silent failure was causing problems for diagnosing issues. This PR changes the behaviour so that an error is thrown.
This will break generators which rely on the previous behaviour. Several of our demo blocks needed editing to accomodate this change.
Resolves#7665
* chore: delete mocha tests for angle field
* feat! : delete angle field
* chore(tests): delete colour tests from generator tests and golden files
* chore: delete colour blocks and associated generators
* chore: remove colour blocks from playgrounds
* chore: delete mocha tests for colour fields
* chore: fix incorrect comment
* chore: delete colour field from core
* chore: delete multiline input tests from generators tests and golden files
* chore: delete multiline text block and associated generators
* chore: remove multiline text block from playgrounds
* chore: delete mocha tests for multiline input field
* chore: delete multiline input field from core
* refactor(generators): Migrate lua_generator.js to TypeScript
* refactor(generators): Migrate generators/lua/* to TypeScript
* fix(generators): Fix type errors in generator functions
* refactor(generators): Migrate generators/lua.js to TypeScript
* chore(generator): Format
* chore(generators): JSDoc and formatting tweaks for PR #7654
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Co-authored-by: Christopher Allen <cpcallen+git@google.com>
