Help output for `dotnet build` appears misleading

### Describe the bug

The output of `dotnet build -h` includes:

```
dotnet build [...] [options]
```

According to the [Posix Utility Standard](https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap12.html#tag_12_02) #9, the ellipses would indicate that multiple Projects, etc. could be used. It is not legal to use multiple projects, and I assume not legal to use multiple solutions, and the text indicates you can only use one C# file (file based apps).

If there is a reason an array of strings is accepted, and this declaration is created via System.CommandLine, it may be difficult to remove the ellipses. Thus, I suggest the text be reconsidered, such as frequent use of the phrase "a single", as the current phrasing is not clear that only one is allowed:

```
The project or solution or C# (file-based program) file to operate on. If a file is not specified, the command will search the current directory for a project or solution.
```

Start by running `dotnet build -h` and reading the help definition for the build command, including the System.CommandLine usage if it is involved. Confirm how the target argument is rendered and update the wording so the help makes clear that only one project, solution, or C# file is accepted; verify the resulting help output.

Written by the indexing model from the issue text.