HPCC-12107 Segmentation fault when supplying an incorrect Wuid to
DATASET(WORKUNIT(...

Add code to check and convert 'w' to 'W' into secOpenWorkUnit()
Add code to check first character of the WUID into same function

Add code to check the return value of factory->openWorkUnit() to avoid
SEGFAULT caused by zero pointer.

Signed-off-by: Attila.Vamos <attila.vamos@gmail.com>
HPCC-12107 Segmentation fault when supplying an incorrect Wuid to
DATASET(WORKUNIT(...

Update after review.

Signed-off-by: Attila.Vamos <attila.vamos@gmail.com>
HPCC-12107 Segmentation fault when supplying an incorrect Wuid to
DATASET(WORKUNIT(...

Update after second review.

Signed-off-by: Attila.Vamos <attila.vamos@gmail.com>
Merge pull request #6379 from AttilaVamos/HPCC-12107-fix

HPCC-12107 Segmentation fault when supplying an incorrect Wuid to DATASET(WORKUNIT(...

Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>