fdo#74507: Write test for this to induce the crash during unit test run.

Change-Id: Ib25136c203f7da17a9b7f086916d870225bc729b
fdo#74507: Ensure that we have non-null pointer to ScColumn.

Else it would cause a null pointer dereferencing when "precision as shown"
option is set.

Change-Id: Ie8d2fdb916b575fff7e0217c45c18a2c799577cb