[top/dv] increase test timeout
[top/dv] increase test timeout

- the keymgr functional tests goes through multiple reset cycles
  and thus may incur a larger run-time especially since clocks
  are uncalibrated upon power up

Signed-off-by: Timothy Chen <d7b2ae30d8c0f215facd721941273067fd1d14a2@google.com>

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