Weird lines and cutoff italics with JetBrains Mono
#### 🗹 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
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#### 🎯 Subject of the issue

Experienced behavior:
<!-- Describe issue here -->
I get lines in between character (for powerline icons) and cutoff icons and italics

Expected behavior:
<!-- Please do not forget to explain what you would have expected to see -->
I would have expected them to not have lines and cutoff icons. I think the lines are just the background color of the character so it might be anti aliasing issue. I have found some similar issues on here but I do not know how to patch my own font so I cannot use their solution.

Example symbols:
<!-- The codepoint of one or more affected symbols, or paste the text containing the issue here (no screenshot) -->
Mostly Powerline symbols having lines as well cutoff icons and italics

#### 🔧 Your Setup

- _Which font are you using (e.g. `Anonymice Powerline Nerd Font Complete.ttf`)?_
   - JetBrainsMonoNLNerdFontMono-Regular.ttf
- _Where did you get the file from (download link, self patched, source downloaded from link...)_
   - I have tried both the github repository and a repository from pacman
- _Which terminal emulator are you using (e.g. `iterm2`, `urxvt`, `gnome`, `konsole`)?_
   - xterm
- _Are you using OS X, Linux or Windows? And which specific version or distribution?_
   - Linux - Endeavor Os

#### ★ Screenshots (Optional)

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![2023-09-25-14:08:06-screenshot](https://github.com/ryanoasis/nerd-fonts/assets/107591653/4130622d-cdf8-48d1-97a5-d6eea574a5c6)
![2023-09-06-19:05:36-screenshot](https://github.com/ryanoasis/nerd-fonts/assets/107591653/9d8bbc56-e07c-4aa7-a6d6-f75be225b049)

