fix(core-flows): payment error handling (#13876)

* fix: payment error handling

* Create dirty-radios-kiss.md

* fix: updated to use isMedusaError

* fix: error message updated and error type corrected

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Co-authored-by: William Bouchard <46496014+willbouch@users.noreply.github.com>
Co-authored-by: Carlos R. L. Rodrigues <37986729+carlos-r-l-rodrigues@users.noreply.github.com>

.changeset/dirty-radios-kiss.md

@@ -0,0 +1,5 @@
+---
+"@medusajs/core-flows": patch
+---
+
+fix(core-flows): payment error handling