Dependabot Fails with update_not_possible for a package Despite No Configuration Changes

### Is there an existing issue for this?

- [x] I have searched the existing issues

### Package ecosystem

Nuget

### Package manager version

NuGet CLI 6.x

### Language version

NET 8 / C#

### Manifest location and content before the Dependabot update

Server/xxxx.HMI.App.xxxx.BE/xxxxx.HMI.App.xxxx.BE.csproj

### dependabot.yml content

```
version: 2
updates:
- package-ecosystem: "nuget"
directories:
- "/BackEnd"
target-branch: "main"
labels:
- "Nuget dependencies"
commit-message:
prefix: "Nuget Dependency Update"
include: "scope"
groups:
project-server-dependencies:
applies-to: version-updates # Applies the group rule to version updates
patterns:
- "Aggregates.Config"
- "Aggregates.Client"
- "Aggregates.ObjDir"
- "xxxxx.OpcUaServer"
ignore:
- dependency-name: 'LiteDB'
- dependency-name: 'Microsoft.*'
- dependency-name: 'NWebsec.AspNetCore.Middleware'
- dependency-name: 'Newtonsoft.Json'
- dependency-name: 'OpenTelemetry.*'
- dependency-name: 'Serilog.*'
- dependency-name: 'StyleCop.Analyzers'
- dependency-name: 'Swashbuckle.*'
- dependency-name: 'System.IdentityModel.Tokens.Jwt'
- dependency-name: 'xunit'
- dependency-name: 'xunit.*'
- dependency-name: 'SolidToken.SpecFlow.DependencyInjection'
- dependency-name: 'AutoFixture'
- dependency-name: 'AutoFixture.*'
- dependency-name: 'coverlet.*'
- dependency-name: 'IdentityModel'
open-pull-requests-limit: 2
registries:
- azure_artifacts

registries:
azure_artifacts:
type: "nuget-feed"
url: "https://pkgs.dev.azure.com/{org}/{proj}/_packaging/{feedname}/nuget/v3/index.json"
token: PAT:${{TOKEN}}
````

```
- task: dependabot@2
displayName: Run Dependabot on ${{repositoryName.name}}
continueOnError: true
inputs:
targetRepositoryName: ${{repositoryName.name}}
setAutoComplete: false
mergeStrategy: 'squash'
autoApprove: false
autoApproveUserToken: $(DEPENDABOT_PAT)
azureDevOpsAccessToken: $(DEPENDABOT_PAT)
experiments: 'nuget-use-legacy-updater-when-updating-pr: false'
timeoutInMinutes: 30
env:
TOKEN: $(DEPENDABOT_PAT)
```

### Updated dependency

Dependency: xxxxx.OpcUaServer
Error: update_not_possible

Current version is eg 1.0.78, new version avaolable is 1.0.88

### What you expected to see, versus what you actually saw

Expected:
Dependabot should successfully update the xxxxx.OpcUaServer dependency, as it did 10 days ago with the same configuration.

Actual:
Dependabot fails with the following error:
```
{"data":{"error-type":"update_not_possible","error-details":{"dependencies":["xxxxx.OpcUaServer"]}},"type":"record_update_job_error"}
```

### Native package manager behavior

NA

### Images of the diff or a link to the PR, issue, or logs

Adding BOM to [Server/xxxx.HMI.App.xxxx.BE/xxxxx.HMI.App.xxxx.BE.csproj].
{"data":{"error-type":"update_not_possible","error-details":{"dependencies":["xxxxx.OpcUaServer"]}},"type":"record_update_job_error"}
updater | 2025/07/04 05:14:56 INFO Handled error whilst updating xxxxxx.OpcUaServer: update_not_possible {dependencies: ["xxxxxx.OpcUaServer"]}

updater | +------------------------------------------------------------------------------------------------------------------------------------+
updater | | Changes to Dependabot Pull Requests |
updater | +---------+--------------------------------------------------------------------------------------------------------------------------+
updater | | created | Microsoft.AspNetCore.Authentication.JwtBearer ( from 8.0.16 to 8.0.17 ), Microsoft.IdentityModel.Protocols.OpenIdConn... |
updater | +---------+--------------------------------------------------------------------------------------------------------------------------+
updater | Dependabot encountered '1' error(s) during execution, please check the logs for more details.
updater | +------------------------------------------------------+
updater | | Dependencies failed to update |
updater | +--------------------------------+---------------------+
updater | | xxxxx.OpcUaServer | update_not_possible |
updater | +--------------------------------+---------------------+
cli | 2025/07/04 05:15:47 updater failure: updater exited with code 1
##[error]Dependabot failed with exit code 1
##[error]Update tasks failed. Check the logs for more information


### Smallest manifest that reproduces the issue

Contents of Server/xxxx.HMI.App.xxxx.BE/xxxxx.HMI.App.xxxx.BE.csproj


Start with the NuGet updater entry point and the update_not_possible log for xxxxx.OpcUaServer. Reproduce against the supplied dependabot.yml and Server/xxxx.HMI.App.xxxx.BE/xxxxx.HMI.App.xxxx.BE.csproj, then compare the failed 1.0.78-to-1.0.88 update with the successful run from 10 days earlier. Done means the failure is explained and the dependency update path is verified or a focused regression test demonstrates the fix.

Written by the indexing model from the issue text.