docs: added spec for 'incomingPaymentCreated' and schema for 'amount' in webhooks.yaml #1294

Job	Run time
prerequisite	41s
version-generator	8s
docker-build (linux/amd64, amd64, auth)	1m 10s
docker-build (linux/amd64, amd64, backend)	1m 16s
docker-build (linux/amd64, amd64, frontend)	1m 29s
docker-build (linux/arm64, arm64, auth)	4m 15s
docker-build (linux/arm64, arm64, backend)	5m 3s
docker-build (linux/arm64, arm64, frontend)	4m 15s
frontend	35s
backend	4m 58s
auth	1m 32s
codeql-analyze (javascript, ./.github/codeql/source.yml)	2m 34s
graphql (auth)	2m 29s
integration-test	2m 29s
codeql-analyze (javascript, ./.github/codeql/tests.yml)	2m 6s
mock-account-servicing-entity	37s
graphql (backend)	2m 35s
token-introspection	37s
Docker Grype Scan (linux/amd64, amd64, auth)	13s
Docker Trivy Scan (linux/amd64, amd64, auth)	10s
Docker Grype Scan (linux/amd64, amd64, backend)	16s
Docker Trivy Scan (linux/amd64, amd64, backend)	12s
Docker Grype Scan (linux/amd64, amd64, frontend)	15s
Docker Trivy Scan (linux/amd64, amd64, frontend)	13s
Docker Grype Scan (linux/arm64, arm64, auth)	14s
Docker Trivy Scan (linux/arm64, arm64, auth)	13s
Docker Grype Scan (linux/arm64, arm64, backend)	14s
Docker Trivy Scan (linux/arm64, arm64, backend)	8s
Docker Grype Scan (linux/arm64, arm64, frontend)	15s
Docker Trivy Scan (linux/arm64, arm64, frontend)	10s
node-build	32s
Push to registry	0s
generate-release	0s
	41m 54s

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