Overriding Configuration at Runtime for Linux Elastic Premium Plan does not work when using Environment variable with dot such as "Host.Triggers.DurableTask.AzureStorage"

When we add the below app setting to override monitoring configuration it does not work.

AzureFunctionsJobHost__logging__logLevel__Host.Triggers.DurableTask = Warning.

### **Expected Behavior :**

LoggerFilterOptions
{
"MinLevel": "None",
"Rules": [
{
"ProviderName": null,
"CategoryName": "Host.Triggers.DurableTask",
"LogLevel": "Warning",
"Filter": null
}

### **Actual Behavior:**

LoggerFilterOptions
{
"MinLevel": "None",
"Rules": [
{
"ProviderName": null,
"CategoryName": "Host_Triggers_DurableTask",
"LogLevel": "Warning",
"Filter": null
}

----------------------------------------------------------------------------------------------

So the . is replaced with _ for environment variable which is expected for this change done few years back.

[PR 1323668](https://msazure.visualstudio.com/One/_git/AAPT-Antares-Websites/commit/2726de3e4c4cadf9b21a5db78753b232d5db3872?refName=refs%2Fheads%2Fdev)

For this change host is not recognizing the environment variable as the category name to override (Host_Triggers_DurableTask versus Host.Triggers.DurableTask). The above change can't be reverted as . is not allowed character in Linux and was causing other conflicting issues.

Hence we need to make changes for the host to recognize environment variables with _ in Linux EP or Dedicated plan.

Start by reproducing the Linux Elastic Premium configuration with AzureFunctionsJobHost__logging__logLevel__Host.Triggers.DurableTask and compare the resulting LoggerFilterOptions with the expected category name. Trace how environment-variable underscores are mapped to logging category names; done when Linux EP or Dedicated plan settings recognize the intended Host.Triggers.DurableTask category without breaking the existing dot restriction.

Written by the indexing model from the issue text.