No easy way for a regular user to lock the tabs, except one at a time. Use the way RacerX indicates
The setting is held in the user profile file sessionrc, if the tab is locked there is an entry added (locked)
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(dockable "gimp-tool-options"
(locked)
(tab-style automatic)
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It might be possible to use a bash / bat file to add that entry above every occurrence of (tab-style automatic) but really, just use the Gimp interface. A good opportunity to close all those tabs you never use