Move actions tests to separate files

[Ekrekr]

Bit hard to review sorry, but good to get over with! All the same tests remain, apart from a duplicate test for disabled options, but just moved. Plus some shared library changes.

I also want to:

• make these tests separate build targets, following Google standards, but I can't until resolving some circular dependencies.
• Have config options for YAML, SQLX, and the JS API merged.

[Ceridan]

Could you please explain what is the current responsibility of main_test.ts?

[Ekrekr]

I think pretty much everything could be moved to separate test files!

So currently it's mainly a proxy for testing session, because session doesn't really work without the code in main. But this could all moved under a session_test.ts file.

Things like SQLX testing in here are needed here because the literal JS parsing during SQLX compiling changes when passed through all the layers like this:

dataform/core/compilers.ts

Line 85 in 3035b54

function compileSqlx(rootNode: SyntaxTreeNode, path: string): string {

. But they could be moved under compilers_test.ts, and call the methods in run_core.ts, like the actions tests do now.

Workflow settings could be moved to workflow_settings_test.ts, and general action configs tests could be moved to actions/index_test.ts.