[SCB-468] Add notice for vertx 3.5.1

[yangbor]

This is related to SCB-459 which upgraded vertx to 3.5.1.

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[coveralls]

Coverage decreased (-0.3%) to 87.481% when pulling 6935f7f on yangbor:master into 4f8f810 on apache:master.

[wujimin]

vert-x3/vertx-web#906

will rollback to 3.5.0

[yangbor]

Close this PR due to rollback to vertx 3.5.0

[WillemJiang]

We need to revisit this issue once we upgrade the vertx version.