Fail to execute “Execute Function Now…” for slot in Java 25 Function App created with “Managed Identity” authentication type

[v-ruizh]

OS: Win 11
Build Version: 20260302.1

Repro Steps:

1. Create a Java 25 project with "http" template.
2. Create an advanced Java 25 function app with "Managed identity" authentication type.
3. Create a slot for the function app.
4. Deploy the project to the slot.
5. Expand the slot -> Expand "Functions" node -> Right click "http" function -> Click "Execute Function Now..." -> Execute it with the default value.
6. Check whether succeeds to execute the action.

Expect:
Succeed to execute the action.

Actual:
Fail to execute the action.

More Info:
Another error occurs for slot in Windows Java 25 Premium function app with "Secrets" authentication type.

[MicroFish91]

Consider when implementing #4917