Removing code that leads to an exception when retrieved device count is 0

[ruwany]

Purpose

When retrieving devices, there should be no error thrown when device count is 0

Goals

When navigating to the store in APPM, whilst 0 devices are enrolled in IoT Server, when the UI loads, there is an error thrown. This will rectify the issue.

Approach

Removed DeviceManagementException thrown when retrieved device count is 0

User stories

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Release note

Fixed exception thrown when device count is 0

Documentation

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Training

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Certification

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Marketing

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Automation tests

• Unit tests

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• Integration tests

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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

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Learning

N/A.