[Documentation] Link to examples within a Example: block

[harshil21]

Currently in our documentation we group the links to both examples and other references together:

.. seealso::
    :any:`Raw API Bot Example <examples.rawapibot>`
    :attr:`telegram.ext.Updater.bot`,
    `Your First Bot <https://github.com/...>`_

I propose to separate the two, i.e.:

Examples:
    .. code-block:: python

        app.add_handlers(...)

    :any:`Raw API Bot Example <examples.rawapibot>`

.. seealso::
    :attr:`telegram.ext.Updater.bot`,
    `Your First Bot <https://github.com/...>`_

Original ref

#3306 (comment)

[harshil21]

@lemontree210 assigning you. (github doesn't let me assign you so commenting)