Add MacBook Air M1 8-Core 3.2 / 8-Core GPU 13" w/ Xcode 12.4

```
  Model Name:	MacBook Air
  Model Identifier:	MacBookAir10,1
  Chip:	Apple M1
  Total Number of Cores:	8 (4 performance and 4 efficiency)
  Memory:	8 GB
  System Firmware Version:	6723.81.1
  Serial Number (system):	FVFF91M9Q6L8
  Hardware UUID:	AF9C6236-E2E7-5B73-A553-619C3411576C
  Provisioning UDID:	00008103-0001511E3E8A001E
  Activation Lock Status:	Disabled
```

Author: dblandin

Readme.md

@@ -20,6 +20,7 @@ Xcode 12
 |🖥  | iMac Pro 27" (Late 2017) | 3.2 GHz 8-Core Intel Xeon W | 32 GB | 0:33 | 0:07 | 12.2 | 2020-12-07 ([commit](https://github.com/artsy/eidolon/commit/160767463524fb0219dc08552e9fe38023bd63b2)) |
 |💻 | MacBook Air (Late 2020) | Apple M1 | 16 GB | 0:33 | 0:06 | 12.2 | 2020-12-07 ([commit](https://github.com/artsy/eidolon/commit/160767463524fb0219dc08552e9fe38023bd63b2)) |
 |💻 | MacBook Air (Late 2018) | I5-8210Y (1.6 GHz) | 8 GB | 2:15 | 0:20 | 12.2 | 2020-12-07 ([commit](https://github.com/artsy/eidolon/commit/160767463524fb0219dc08552e9fe38023bd63b2)) |
+|🖥 | MacBook Air (Late 2020) | Apple M1 | 8 GB | 0:20 | 0:08 | 12.4 | 2021-3-13 ([commit](https://github.com/artsy/eidolon/commit/c76879a80bce4c23dd66554a3fe24a6a6a93a341)) |
 
 Xcode 11
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