LU-17056 tests: force osc import reconnect in sanity-sec 30b

LU-17056 tests: force osc import reconnect in sanity-sec 30b

In sanity-sec test_30b, force reconnect of idle osc imports
so that security flavor is correctly updated.
In case of failure, dump more information about state of the imports
and the srpc connections.

Lustre-change: https://review.whamcloud.com/54349
Lustre-commit: fa2cfb49decf3d897f63023c998a23fd98c5c3ea

Test-Parameters: trivial
Signed-off-by: Sebastien Buisson <sbuisson@ddn.com>
Change-Id: Iaecc7321b12e61a266e97d3640a3288f0e7ec9dd
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Jian Yu <yujian@whamcloud.com>
Reviewed-on: https://review.whamcloud.com/c/ex/lustre-release/+/54657
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>