[Bug]: Functionality related to capturing stdout/stderr is not documented

[i-ky]

Describe the issue

CaptureStdout(), GetCapturedStdout(), CaptureStderr() and GetCapturedStderr() are not mentioned in the docs/.

Steps to reproduce the problem

1. Look for these functions in GitHub repo.
2. Note that nothing is found in docs/.

I am assuming that they are not mentioned on the home page as well, but this is difficult to check since it does not have a search.

What version of GoogleTest are you using?

1.15.0

What operating system and version are you using?

Ubuntu 22.04

What compiler and version are you using?

GCC 11.4.0

What build system are you using?

CMake 3.29.7

Additional context

No response