[master] Fix providing error message for openapi spec generation when bal service has compilation issues

[lnash94]

Purpose

Fixes ballerina-platform/ballerina-library#5134

Automation tests

• Unit tests - added

  Code coverage information

• Integration tests

  Details about the test cases and coverage

Security checks

• Followed secure coding standards in http://wso2.com/technical-reports/wso2-secure-engineering-guidelines? yes/no
• Ran FindSecurityBugs plugin and verified report? yes/no
• Confirmed that this PR doesn't commit any keys, passwords, tokens, usernames, or other secrets? yes/no

Samples

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Related PRs

New PR for align with new structure changes
Ref : #1370

Migrations (if applicable)

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Test environment

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Learning

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[sonarqubecloud]

Quality Gate failed

Failed conditions
7.3% Duplication on New Code (required ≤ 3%)

See analysis details on SonarCloud