fix: address serialization in PayForBlobs event #2417

Job	Run time
branch_name	1s
goreleaser-check	9s
lint / golangci-lint	1m 29s
lint / yamllint	8s
markdown-linter / markdown-link-check	1m 50s
markdown-linter / markdown-lint	6s
test / test-short	2m 45s
test / test	15m 38s
test / test-coverage	6m 20s
test / test-race	8m 21s
lint / hadolint / hadolint	8s
version_bump	0s
goreleaser	0s
	36m 55s

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