LU-17265 tests: allow margin for sanity/39r

LU-17265 tests: allow margin for sanity/39r

The timestamp may be little outdated due to a gap between
writing a file and checking the timestamp, so take that into
consideration and allow 2 second leniency when comparing
timestamps.

The on-disk inode may also not be flushed from the journal
immediately, so allow some time for it to be updated.

This patch also converts the hex value read via debugfs
to decimal.

Test-Parameters: trivial testlist=sanity env=ONLY=39r,ONLY_REPEAT=100
Signed-off-by: Arshad Hussain <arshad.hussain@aeoncomputing.com>
Change-Id: I9e765f9cd572fb25821f9a0401c34209b7c3f574
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/53035
Reviewed-by: James Simmons <jsimmons@infradead.org>
Reviewed-by: xinliang <xinliang.liu@linaro.org>
Reviewed-by: Oleg Drokin <green@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>