[INTERNAL] Table: fix _configureAutoPopin spy qunit test
[INTERNAL] Table: fix _configureAutoPopin spy qunit test

The test to check if _configureAutoPopin is called when the importance property
of the column header changed failed since the column already had "High"
importance. The importance were applied randomly to the columns and there
can be chances that the column for which the importance is changed already
has High importance. This ramdomization of importance is removed to stabilize
the qunit test.

Change-Id: I7f425b7cabe1965e37e3acb8eb2afd59e4a759e5

SAP/openui5,SAP/openui5,SAP/openui5,SAP/openui5