LU-13514 tests: replace nid in conf-sanity test_32

LU-13514 tests: replace nid in conf-sanity test_32

Need replace_nid for test_32a. Else the mdc cannot
be initialzed and prevent client mounting hung.

Test-Parameters: trivial
Test-Parameters: env=ONLY=32a,ONLY_REPEAT=20 fstype=ldiskfs testlist=conf-sanity
Signed-off-by: Yang Sheng <ys@whamcloud.com>
Change-Id: I651f5728ad4ff96a309ed599490c9dd6ed9c5274
Reviewed-on: https://review.whamcloud.com/40537
Reviewed-by: Jian Yu <yujian@whamcloud.com>
Reviewed-by: James Simmons <jsimmons@infradead.org>
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>