Fyne package is removing built executables

[andydotxyz]

Checklist

• I have searched the issue tracker for open issues that relate to the same problem, before opening a new one.
• This issue only relates to a single bug. I will open new issues for any other problems.

Describe the bug

The package command is using the build command which will remove existing build files in PWD...

Instead it should build to a temporary directory so we don't overwrite build files or other files with the same name.

Info extracted from a conversation with @hkparker.

How to reproduce

1. fyne build and see your executable
2. fyne package and you will see a package but the executable is gone.

Note that this will not be recognisable on Windows because they have the same file name.

This also happens with conflicting builds for different platforms, such as a Linux host running fyne build and then fyne package -os android.

Screenshots

No response

Example code

n/a

Fyne version

2.5.3 and develop

Go compiler version

all

Operating system and version

macOS/Linux

Additional Information

No response

[Jacalz]

I wonder if this should be in the tools repo instead? I think we really need to double down and do that transition for v2.6.0 if we want to move towards a v3.0.0 and be able to clean out the command from this repo by then.

[hkparker]

I originally noticed that fyne package, when creating an android app on linux, was deleting the linux binary, I just now noticed that fyne serve on linux deletes the binary as well.

[Jacalz]

Yes, all of them build to the current directory. Should be quite an easy fix, I think