RSDK-7848 remove side-by-side meta.json support

[abe-winter]

What changed

• remove side-by-side support from Module.EvaluateExePath and Module.getJSONManifest
• (incidental) automatically MkdirAll in testWriteJSON

Why

Side-by-side mode was an RDK feature that we rushed in order to support local modules under the odd execution rules of android OS. We fast-followed with meta-in-tarball which is now the standard. Side-by-side has been deprecated for a while; I'm removing now because APP-8193 requires touching these code paths, and will be simpler without the third case.

How they differ:

• side-by-side mode means that a meta.json file is next to a local tarball, e.g. you have a mymodule/module.tar.gz and a mymodule/meta.json next to it
• meta-in-tarball means that there is a meta.json inside the tarball at the root level. This is necessary in the local tarball case, and optional in the registry case; when present for registry modules, the meta-in-tarball entrypoint field takes precedence over what's specified in cloud

[jmatth]

Code LGTM but one question: will shipping this potentially break existing deployments and if so are we ok with that? I saw in the description you said this feature has been deprecated for a while and presumably not used outside of Android so I'm guessing this is ok to ship but just wanted to be certain.

[abe-winter]

will shipping this potentially break existing deployments

good call, will investigate before merging

[cheukt]

LGTM % josh's comment