Fixing regression issues for the validations

[rasika]

Purpose

Adding additional validations to improve stability of the product and fixing regression issues. Resolves https://github.com/wso2/product-iots/issues/1624

Goals

Improving the stability of the product.

Approach

Added relevant fixes to improve stability of the product

User stories

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Release note

Added additional validations to improve stability of the product

Documentation

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Training

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Certification

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Marketing

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Automation tests

• Unit tests

  N/A

• Integration tests

  N/A

Security checks

• Followed secure coding standards in http://wso2.com/technical-reports/wso2-secure-engineering-guidelines? yes
• Ran FindSecurityBugs plugin and verified report? yes
• Confirmed that this PR doesn't commit any keys, passwords, tokens, usernames, or other secrets? yes

Samples

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Related PRs

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Migrations (if applicable)

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Test environment

Maven home: /usr/local/Cellar/maven/3.5.2/libexec Java version: 1.8.0_141, vendor: Oracle Corporation Java home: /Library/Java/JavaVirtualMachines/jdk1.8.0_141.jdk/Contents/Home/jre Default locale: en_US, platform encoding: UTF-8 OS name: "mac os x", version: "10.13.2", arch: "x86_64", family: "mac"

Learning

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