Improve serialization and deserialization of clipboard content on client side

[PMohanJ]

Reference the issue numbers and reviewers Use # and @ to tag issues and reviewers. @ehfd

Explain relevant issues and how this pull request solves them Improves serialization and deserialization of clipboard content on client side. The methods btoa() and atob() are meant to handle ASCII chars, so if character's code point exceeds 0xff it causes exception. So, we can use TextEncoder and TextDecoder interfaces to handle chars with UTF-8 format more appropriately.

Describe the changes in code and its dependencies and justify that they work as intended after testing Changes are primarily on web interface(gst-web) where the messages sent/received though datachannel for the clipboard read and write events are handled furtherly to support UTF-8 encoding format.

Describe alternatives you've considered NA

Additional context NA

• [x] I confirm that this pull request is relevant to the scope of this project. If you know that upstream projects are the cause of this problem, please file the pull request there.
• [x] I confirm that this pull request has been tested thoroughly and to the best of my knowledge that additional unintended problems do not arise.
• [x] I confirm that the style of the changed code conforms to the overall style of the project.
• [x] I confirm that I have read other open and closed pull requests and that duplicates do not exist.
• [x] I confirm that I have justified the need for this pull request and that the changes reflect the fix for the specified problem.
• [x] I confirm that no portion of this pull request contains credentials or other private information, and it is my own responsibility to protect my privacy.

[ehfd]

@PMohanJ Please resolve conflict triggered by revert.