Problem
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Before, the default tax for sale and purchase was: GST 5%. Commit
084408a9bb, modfied by accident the
default tax to IGST 18%.
Objective
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Revert the deault taxes back to GST 5%.
Solution
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Update the default taxes in the l10n_in template file.
task-3634577
closes odoo/odoo#146809
Signed-off-by: Josse Colpaert <jco@odoo.com>