chore(dev-deps): bump @oclif/plugin-help from 6.2.4 to 6.2.6 #618

Job	Run time
yarn-lockfile-check / lockfile-check	10s
linux-unit-tests / determine-node-versions	3s
linux-unit-tests / linux-unit-tests (current)	1m 3s
linux-unit-tests / linux-unit-tests (lts/*)	59s
linux-unit-tests / linux-unit-tests (lts/-1)	1m 6s
sf-integration (lts/*, ubuntu-latest)	56s
sf-integration (latest, ubuntu-latest)	54s
sf-integration (latest, windows-latest)	7m 14s
windows-unit-tests / determine-node-versions	1s
windows-unit-tests / windows-unit-tests (current)	2m 10s
windows-unit-tests / windows-unit-tests (lts/*)	3m 6s
windows-unit-tests / windows-unit-tests (lts/-1)	4m 7s
	21m 49s

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