Add trivy scan for the connector

[nipunayf]

Description

The PR adds Trivy scan for the connector to check and generate the security vulnerability report on demand or during releases.

Related to https://github.com/ballerina-platform/ballerina-extended-library/issues/536

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1 out of 2 committers have signed the CLA.

✅ NipunaRanasinghe
❌ Nipuna Fernando

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