I have been able to find a solution for this. The order in which the js files will be consolidated would be same as mentioned in the group tag as following:
<group name="plugins_grid_filters_feature_types">
<js>/resources/js/plugins/grid/filter/Filter.js</js>
<js>/resources/js/plugins/grid/filter/BooleanFilter.js</js>
<js>/resources/js/plugins/grid/filter/DateFilter.js</js>
</group>
Here all the above files are in the same folder & are part of same group. Also, alphabetically BooleanFilter.js appears before Filter.js, but for project Filter.js should be accessed before BooleanFilter.js, thus, for this the expected order should be mentioned in the group tag as shared above.
Hope this helps someone looking for the same.
Thanks again to Alex and everyone else associated with this wonderful project.
Regards