Update dav.rst

fixed dashes to the length of the text of the title

userguide/advanceduse/dav.rst

@@ -18,9 +18,9 @@ Then choose between the two following guides
 * The one proposed by Bastos77 and Vanyasem is quite simple, if you have few CalDav or CardDAV to configure. 
 * The one proposed by UT-itilities is much featured, with many commands to create or delete configurations. Use it if you manage many configurations, on one or multiple servers
 
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 1. A simple guide proposed by `Bastos77 <https://gist.github.com/bastos77>`_ and `Vanyasem <https://gist.github.com/vanyasem>`_
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 #. Download this `script <https://gist.github.com/vanyasem/379095d25ac350676fc70c42efe17c8c>`_ (let's call it dav.sh) and edit the following variables: 
 
    *  ``CAL_URL``
@@ -42,9 +42,9 @@ Then choose between the two following guides
         chmod +x dav.sh
         ./dav.sh
 
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 2. Or a full featured guide proposed by `UT-ilities <https://github.com/UT-ilities>`_
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 if you have many configurations on one or multiple Caldav/CardDav servers