Wrong Content-Type is sent when connecting to Account Manager

[N0vas]

Describe the bug
When BOINC is connecting to an account manager, it sends XML data "acct_mgr_request" to "URL/rpc.php" and sets the Content-Type to "application/x-www-form-urlencoded".

Expected behavior
The Content-Type header should be set to text/xml or application/xml to reflect the data that it is being sent.

Steps To Reproduce

1. Attach BOINC Client to an account manager
2. Look at the sent request to rpc.php and notice wrong Content-Type

System Information

• OS: Ubuntu 22.04 LTS
• BOINC Version: 7.18.1 (Ubuntu won't give me something newer)

Additional Context
I want to create a custom Account Manager, so I was exploring the interfaces etc. After some testing I noticed that the Content-Type is not matching the data that is being sent on the initial "acct_mgr_request" from the client. That is a problem when I try to identify valid requests to rpc.php endpoint.