Extra facets added for EMAC to map o3, tro3 and aps

[FranziskaWinterstein]

Description

This pull request introduces extra facets in emac-mappings.yml so that the variables for O3 (o3 and tro3) are found. This makes it also possible to apply the derived variable toz.

Checklist

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• [x] 🧪 The new functionality is relevant and scientifically sound
• [x] 🛠 This pull request has a descriptive title and labels
• [x] 🛠 Code is written according to the code quality guidelines
• [x] 🧪 and 🛠 Documentation is available
• [x] 🛠 Unit tests have been added
• [x] 🛠 Changes are backward compatible
• [x] 🛠 Any changed dependencies have been added or removed correctly
• [x] 🛠 The list of authors is up to date
• [x] 🛠 All checks below this pull request were successful

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 94.70%. Comparing base (ecb01b3) to head (baf0fd6).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #2501 +/- ## ======================================= Coverage 94.70% 94.70% ======================================= Files 249 249 Lines 14114 14114 ======================================= Hits 13367 13367 Misses 747 747 ```

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