`Component diagrams`: Fix an appearance issue with interface connections

[minrows]

Checklist

• [x] I added multiple screenshots/screencasts of my UI changes

Motivation and Context

This PR removes the white triangles issue in the interface connection of the component diagram. Issue Number: https://github.com/ls1intum/Apollon/issues/251

Steps for Testing

In local machine

1. Clone the repo
2. Checkout to bugfix/component-diagram-interface-fix branch
3. Run the application by executing yarn install followed by yarn start commands
4. Select Component Diagram from Diagram Type Menu
5. Add Component and Interface to the canvas and connect them together, as illustrated in the screenshots
6. Observe there are no white triangles on the background of connectors

In test server

• Goto test server
• Create New ComponentDiagram by clicking on File > New > ComponentDiagram
• Add Component and Interface to the canvas and connect them together, as illustrated in the screenshots
• Observe there are no white triangles on the background of connectors

Screenshots

Before

After

Additional Info:

Changes included in 2.11.2-beta.0

Todo:

• [x] Deploy in Test server