DOCS: Add link to 19.08 test framework docs
DOCS: Add link to 19.08 test framework docs

Change-Id: Ib0c3e3376152f4ec04e3689fb9ed94a859f1022f
Signed-off-by: Dave Wallace <0ed937c0e4b2f09f7bc24acf16cee52b8a199d5f@gmail.com>

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