[Premium] WEBSITE_RUN_FROM_PACKAGE=1 no longer works correctly

**Describe the bug**
As of approximately some time last week, linux Function Apps running on standard App Service plans (Basic, Standard, Premium, etc) no longer seem to inspect or respect the packagename.txt file

I have been using linux function apps for the last 3 years using WEBSITE_RUN_FROM_PACKAGE=1 and using either ZipDeploy or other methods such as SSH, FTP, VFS to upload zip packages and update the packagename.txt file

https://learn.microsoft.com/en-us/azure/azure-functions/run-functions-from-deployment-package
https://learn.microsoft.com/en-us/azure/app-service/deploy-ftp?tabs=portal#what-happens-to-my-app-during-deployment
https://learn.microsoft.com/en-us/azure/app-service/deploy-run-package#run-the-zip-package

**To Reproduce**
Steps to reproduce the behavior:
1. Go to `Function Apps` in Azure (https://portal.azure.com/#browse/Microsoft.Web%2Fsites/kind/functionapp)
2. Click on `Create`
3. Select `App Service
4. Create a `linux` `Node.js` `20 LTS` plan using `P0V3` Plan
5. After creating, enable WEBSITE_RUN_FROM_PACKAGE=1
6. Deploy a package using ZipDeploy
7. Verify deployment
8. Upload a different zip package to the /home/data/SitePackages directory
9. Update the packagename.txt file to this new file
10. Observe that the new package is not loaded and the function app is not restarted
11. Restart the function app and the new package is not used even though packagename.txt is updated

Updating packagename.txt with invalid characters, invalid zip or valid zip file has no effect.
With invalid characters, I would expect to see something like: `RunFromPackage> Error Invalid binding. Only alphanumeric characters and "." allowed.`

**Expected behavior**
The function app should respect the packagename.txt file and changes to the file

**Screenshots**
If applicable, add screenshots to help explain your problem.

**Additional context**
This seems to only occur for linux function apps using WEBSITE_RUN_FROM_PACKAGE=1
WEBSITE_RUN_FROM_PACKAGE=[url] works
Windows function apps do not seem to be affected.
Isolated (App Service Environments) and Elastic Premium (EP1) are not affected.