fix: Skip setting existing context values
When setting up a context with user provided variables, we should not override any of the existing values.
Fixes: aurweb-errors#533, aurweb-errors#532, aurweb-errors#497
Edited by Mario Oenning
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When setting up a context with user provided variables, we should not override any of the existing values.
Fixes: aurweb-errors#533, aurweb-errors#532, aurweb-errors#497