✨ subprocess Add support for overriding the stdin/stdout/stderr of a subprocess

[joshjennings98]

Description

Add support for overriding the stdin/stdout/stderr of a subprocess.

Factories are used so that a context can be injected for context aware readers and writers.

Test Coverage

• This change is covered by existing or additional automated tests.
• Manual testing has been performed (and evidence provided) as automated testing was not feasible.
• Additional tests are not required for this change (e.g. documentation update).