[O] angle brackets around timestamps in html export

[Matt Price]

Hello again,

I'm trying to get rid of angle brackets in HTML export.  I've set
org-export-date-timestamp-format to "%a, %b %d".  I also have
timestamp overlays turned on, and the displayed custom format set to
"<%a, %b %d>" (that seems unlikely to be relevant, but I've changed it
just in case).

Sorry I can't find the answer in the docs, I'm sure it's there
somewhere but I'm missing it somehow!

Matt