[master] Fix OpenAPI spec generation issues

[lnash94]

Purpose

Fixes:

1. Fixed included record field overriding issue https://github.com/wso2-enterprise/internal-support-ballerina/issues/831
2. Improvement: mapping constant values as default value in the generated OAS Support constant value expression for the default value mapping in OAS generation ballerina-library#7353

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

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Migrations (if applicable)

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Test environment

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Learning

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[sonarqubecloud]

Quality Gate passed

Issues
5 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud