* Update lea-0.87.0.toml
The choice of GNAT version is improved.
The previous state forced to a version of GNAT which is supported by Alire.
This assumed a GNAT already installed outside of Alire.
Absent that, the build fails.
* Update lea-0.87.0.toml
Indicate that there is an executable built.
This removes the message:
"Crate lea does not explicitly declares to build any executable
However, the following default executables have been autodetected"
* Update lea-0.87.0.toml
Alire seems not to expect a file name extension for the executable:
"Crate lea builds these executables:
lea.exe.exe (not found)"