Mailing Report: hide the HTML preview

[mlutfy]

Overview

When viewing a mailing report, it displays a preview of the HTML. Only so much can be said in 30 characters of HTML, so it looks like this:

I'm pretty sure everyone here just got used to ignoring that "DOCTYPE html PUBLIC" string. I really don't see the purpose of it.

After

Removed the HTML preview, as well as the bold/strong:

[civibot]

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[jitendrapurohit]

I've applied the PR and tested the display of preview on the report page. It does what it aims to remove the preview text from the report screen. The text seems unwanted and don't think it should be displayed.

From git blame, it looks like this was added long back from the initial stage. Either we need to update it to display only the truncated part of body/subject + link OR the current fix looks good which keeps the link to complete message in popup.

[yashodha]

test this please

[yashodha]

@mlutfy @jitendrapurohit looks good, can be merged. Thanks!