NoCloud seedfrom http/s will not be processed before other datasources

# Bug report
NoCloud using `seedfrom` is skipped even when prioritized first.

## Steps to reproduce the problem

VMware (or other providers) work with the following `user-data`:
```
#cloud-config
datasource:
NoCloud: {}
```
^^^ Will correctly load cloud-config from VMware customization specification dashboard.

```
datasource_list: [NoCloud, VMware, None]
datasource:
NoCloud:
seedfrom: https://example.com/cloud-init/
```
^^^ Will skip NoCloud ignoring valid cloud-config and kick VMware without any cloud-config.

## Environment details
- Cloud-init version:
- Operating System Distribution:
- Cloud provider, platform or installer type:

## cloud-init logs

```
2025-12-04 21:58:55,802 - sources[DEBUG]: Searching for local data source in: ['DataSourceNoCloud', 'DataSourceVMware']
2025-12-04 21:58:55,802 - handlers.py[DEBUG]: start: init-local/search-NoCloud: searching for local data from DataSourceNoCloud
2025-12-04 21:58:55,802 - sources[DEBUG]: Seeing if we can get any data from
2025-12-04 21:58:55,802 - sources[DEBUG]: Update datasource metadata and network config due to events: boot-new-instance
2025-12-04 21:58:55,803 - sources[DEBUG]: Detected DataSourceNoCloud
```

```
2025-12-04 21:58:55,916 - DataSourceNoCloud.py[INFO]: DataSourceNoCloud only uses seeds starting with ('/', 'file://') - will try to use https://example.com/cloud-init/ in the network stage.
2025-12-04 21:58:55,916 - performance.py[DEBUG]: Getting metadata took 0.114 seconds
2025-12-04 21:58:55,916 - sources[DEBUG]: Datasource DataSourceNoCloud not updated for events: boot-new-instance
2025-12-04 21:58:55,916 - handlers.py[DEBUG]: finish: init-local/search-NoCloud: SUCCESS: no local data found from DataSourceNoCloud
2025-12-04 21:58:55,916 - handlers.py[DEBUG]: start: init-local/search-VMware: searching for local data from DataSourceVMware
2025-12-04 21:58:55,916 - sources[DEBUG]: Seeing if we can get any data from
2025-12-04 21:58:55,917 - sources[DEBUG]: Update datasource metadata and network config due to events: boot-new-instance
2025-12-04 21:58:55,917 - sources[DEBUG]: Detected DataSourceVMware [seed=None]
2025-12-04 21:58:55,917 - dmi.py[DEBUG]: querying dmi data /sys/class/dmi/id/product_name
2025-12-04 21:58:55,918 - DataSourceVMware.py[DEBUG]: discovered vmware-rpctool: /usr/bin/vmware-rpctool
2025-12-04 21:58:55,918 - DataSourceVMware.py[DEBUG]: discovered vmtoolsd: /usr/bin/vmtoolsd
2025-12-04 21:58:55,918 - DataSourceVMware.py[INFO]: query guestinfo with /usr/bin/vmware-rpctool
2025-12-04 21:58:55,918 - DataSourceVMware.py[DEBUG]: Getting guestinfo value for key metadata
2025-12-04 21:58:55,918 - subp.py[DEBUG]: Running command ['/usr/bin/vmware-rpctool', 'info-get guestinfo.metadata'] with allowed return codes [0] (shell=False, capture=True)
2025-12-04 21:58:55,921 - DataSourceVMware.py[DEBUG]: No value found for key metadata
2025-12-04 21:58:55,922 - DataSourceVMware.py[DEBUG]: Getting guestinfo value for key userdata
2025-12-04 21:58:55,922 - subp.py[DEBUG]: Running command ['/usr/bin/vmware-rpctool', 'info-get guestinfo.userdata'] with allowed return codes [0] (shell=False, capture=True)
2025-12-04 21:58:55,925 - DataSourceVMware.py[DEBUG]: No value found for key userdata
2025-12-04 21:58:55,926 - DataSourceVMware.py[DEBUG]: Getting guestinfo value for key vendordata
2025-12-04 21:58:55,926 - subp.py[DEBUG]: Running command ['/usr/bin/vmware-rpctool', 'info-get guestinfo.vendordata'] with allowed return codes [0] (shell=False, capture=True)
2025-12-04 21:58:55,929 - DataSourceVMware.py[DEBUG]: No value found for key vendordata
```