feaf: introduce RAP_RECURSIVE to check packages recursively and RAP_CLEAN to run cargo clean before check

[zjp-CN]

This PR introduce RAP_CLEAN and RAP_CLEAN environment variables:

Environment variables (Values are case insensitive):

var	default when absent	one of these values	description
RAP_CLEAN	true	ture, false	run cargo clean before check
RAP_RECURSIVE	none	none, shallow, deep	scope of packages to check

For RAP_RECURSIVE:

• none: check for current folder
• shallow: check for current workpace members
• deep: check for all workspaces from current folder

NOTE: for shallow or deep, rap will enter each member folder to do the check.

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Output of this PR: https://github.com/os-checker/os-checker-test-suite/blob/480055aec08e0d607c683d532b44d4e072238f68/rap.md