DAOS-16368 doc: Fix typo in dfuse documentation (#14951)

[jolivier23]

--disable-wb-caching should be --disable-wb-cache

Doc-only: true

Required-githooks: true

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[github-actions]

Ticket title is 'documentation should use --disable-wb-cache, not --disable-wb-caching'
Status is 'In Review'
https://daosio.atlassian.net/browse/DAOS-16368