repair broken lambda patch

repair broken lambda patch

in I4e0b627bfa187f1780dc68ec81b94db1c78f846a the 1.4 version has more
changes than the main version, which failed to get the entire change,
yet the whole thing was merged.   Restore the missing mutex related
code to the main version.

Fixed regression where the fix for :ticket:`8098`, which was released in
the 1.4 series and provided a layer of concurrency-safe checks for the
lambda SQL API, included additional fixes in the patch that failed to be
applied to the main branch. These additional fixes have been applied.

Change-Id: Id172e09c421dafa6ef1d40b383aa4371de343864
References: #8098
Fixes: #9461