Documentation: use enumerated list for 'Talks & Publications'
Documentation: use enumerated list for 'Talks & Publications'

The links should now render in the PDF.

Closes: #660 (Documentation: missing links in BPF guide)
Signed-off-by: Alexander Alemayhu <e46fc836cca3acec03944314d1457c2ae6c68ef3@alemayhu.com>

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