CaskaydiaCove Font Does not Include Any Accent Characters
#### 🗹 Requirements
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- [x] I have searched the [issues](https://github.com/ryanoasis/nerd-fonts/issues) for my issue and found nothing related and/or helpful
- [x] I have searched the [FAQ](https://github.com/ryanoasis/nerd-fonts/wiki/FAQ-and-Troubleshooting) for help
- [x] I have searched the [Wiki](https://github.com/ryanoasis/nerd-fonts/wiki) for help


#### 🎯 Subject of the issue

Experienced behavior:
The CaskaydiaCove Font linked in the [release 2.1.0](https://github.com/ryanoasis/nerd-fonts/releases/tag/v2.1.0) doesn't contain German umlauts.

Expected behavior:
The CaskaydiaCove Font should contain German umlauts as the original Cascadia Code Font does contain them.
Furthermore, running `fontforge -script font-patcher src/unpatched-fonts/CascadiaCode/Regular/CascadiaCode-Regular.otf -c --mono --out .` generates a font which contains German umlauts as well.

Example symbols:
German Umlauts are affected.
However, I'm not sure whether there are more accent characters which are affected.

  - German umlauts
    `äöü`

Update: *All* accent characters are missing

#### 🔧 Your Setup

- _Which font are you using (e.g. `Anonymice Powerline Nerd Font Complete.ttf`)?_
   - Caskaydia Cove Regular Nerd Font Complete Mono
   - _Where did you get the file from (download link, self patched, source downloaded from link...)_
     - This repo's v2.1.0 download: https://github.com/ryanoasis/nerd-fonts/releases/tag/v2.1.0
- _Which terminal emulator are you using (e.g. `iterm2`, `urxvt`, `gnome`, `konsole`)?_
  - Windows Terminal
- _Are you using OS X, Linux or Windows? And which specific version or distribution?_
  - Windows

#### ★ Screenshots (Optional)
![image](https://user-images.githubusercontent.com/7085564/165894592-ab97638b-7297-41c5-9b86-a3a1939689ca.png)
**Ordinary characters compared to their accent counterparts**

![image](https://user-images.githubusercontent.com/7085564/165895499-b63a384d-e7d8-4c4e-92d4-eda111dee8ec.png)
**The same in Windows Terminal**


