Updates paper signature text size (shiptest-ss13#2827)

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## About The Pull Request
it updates the pixel size of signatures used in paper

![imagen](https://github.com/shiptest-ss13/Shiptest/assets/75212565/95ac90ae-2b62-4cae-9845-70c750b7c629)

![imagen](https://github.com/shiptest-ss13/Shiptest/assets/75212565/ede0e93e-7b21-410b-ab7e-fc92233cf57b)


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## Why It's Good For The Game
they are barely readable otherwise

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## Changelog

:cl:
tweak: Modified the pixel size of signatures in paper to 15px
/:cl:

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tgui/packages/tgui/interfaces/PaperSheet.tsx

@@ -918,7 +918,7 @@ export class PreviewView extends Component<PreviewViewProps> {
     let input = document.createElement('input');
     input.setAttribute('type', 'text');
 
-    input.style.fontSize = field.is_signature ? '30px' : `${fontSize}px`;
+    input.style.fontSize = field.is_signature ? '15px' : `${fontSize}px`;
     input.style.fontFamily = fieldData.font || font;
     input.style.fontStyle = field.is_signature ? 'italic' : 'normal';
     input.style.fontWeight = 'bold';