[TOS-653] fix: browsers list duplicates fixed

[akash-nixon]

Description

• Jira : https://testsigma.atlassian.net/browse/TOS-653 The "Available Browsers" are displayed twice and it is overlapping " Last Successful Ping At" info
• Steps for reproduce Start Agent Add Agent and observe in the Agents List page
• Actual The "Available Browsers" are displayed twice and it is overlapping " Last Successful Ping At" info
• Expected The "Available Browsers" shouldn’t be displayed twice and also should not overlap the " Last Successful Ping At" info

  Fix

  added a function getUniqueBrowsersList to remove duplicate browsers in agent page