fix(docs): broken link in top-level README

[gnosek]

What type of PR is this?

Uncomment one (or more) /kind <> lines:

/kind bug

/kind cleanup

/kind design

/kind documentation

/kind failing-test

/kind feature

Any specific area of the project related to this PR?

Uncomment one (or more) /area <> lines:

/area build

/area ci

/area event

/area event_derive

/area plugin

/area plugin_api

/area plugin_derive

/area plugin_tests

What this PR does / why we need it:

Fix the doc link on the front page. Again :)

Which issue(s) this PR fixes:

Fixes #

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

NONE

[mrgian]

/lgtm

[poiana]

LGTM label has been added.

Git tree hash: 110368da7f0d3bfa1c240a9418462977c7988f7f

[poiana]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: gnosek, mrgian

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