Update client version field in PDF reports and local UI app details page

[rutujaac]

Update Pebblo Client Version Key:

1. Pebblo Local UI:

2. Show pebbloClientVersion if client version does not exist (backward compatibility):

3. Reports - weasyprint report PDF:

• Show nothing if client version does not exist (backward compatibility):

4. Reports - xhtml2pdf report PDF:

• Show nothing if client version does not exist (backward compatibility):

[shreyas-damle]

We need to remove client version from xhtml2pdf reports.