Add TZ in iTip REPLY iTip messages

[renaudboyer]

Add VTIMEZONE objects in iTip REPLY if there were present in the original message.

Allows to have well-formatted iTip REPLY messages

[codecov]

Codecov Report

Merging #465 into master will increase coverage by 0.01%.
The diff coverage is 100%.

@@             Coverage Diff              @@
##             master     #465      +/-   ##
============================================
+ Coverage     98.86%   98.87%   +0.01%     
  Complexity     1815     1815              
============================================
  Files            65       65              
  Lines          5179     5178       -1     
============================================
  Hits           5120     5120              
+ Misses           59       58       -1

Impacted Files	Coverage Δ	Complexity Δ
lib/ITip/Broker.php	99.54% <100%> (+0.22%)	154 <0> (ø)	⬇️

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[Julian1998]

@DeepDiver1975 Can you merge this one?

[DeepDiver1975]

Looks good to me - I'd like to have a second pair of eyes - @staabm maybe? THX

[staabm]

@evert should have a look. I am not an expert in this area

[m-a-v]

I still haven't managed to get correct REPLY for Microsoft Outlook or Google invitations (if sent as attendee). Should this work with this fix?

[Julian1998]

@m-a-v Can you validate your ics and tell what happened wrong by using https://icalendar.org/validator.html

Not sure what you mean by getting a correct REPLY in this context. But this is a fix for several clients which fail when rendering an event with a TZID set (and the VTIMEZONE object misses ofc)

[renaudboyer]

We were working on Microsoft/Google compatibility issues when we've done this fix. I don't remember which brand was rejecting the reply messages because of invalid format.
If you're using TZ, it should fix your replies.

[DeepDiver1975]

@evert should have a look. I am not an expert in this area

@evert any chance to have a look at this? THX a lot

[evert]

Eying this, this looks good. Awesome that compatibility is still improving