Squish Tests: Configuration default synoptic behaviour

As a developer I would like to verify the following behaviour using Squish:

- Create a synoptic and add it to a configuration as a default synoptic.
- Verify that the default synoptic has updated.
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- Edit the default synoptic of a configuration.
- Verify that the default synoptic has updated.
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- Delete the default synoptic of a configuration.
- Verify that the configuration no longer has a default synoptic.
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- Create a new configuration and set a default synoptic.
- Verify that the default synoptic is set.
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- Verify that the default synoptic is the one selected when the `Synoptic` perspective is opened.
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- Switch to a configuration with a different default synoptic and with the `Synoptic` perspective open.
- Verify that the selected synoptic in the `Synoptic` perspective changes.
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- Change the selected synoptic in the `Synoptic` perspective to something other than the default one.
- Press the `Load Default` button.
- Verify that the selected synoptic changes to the default one.