`VerbAttribute` has unnecessary breaking changes between 2.8.0 and 2.9.1

**Describe the bug**
`VerbAttribute`'s constructor signature has changed between 2.8.0 and 2.9.1. There is a default value for the new alias parameter, so recompilation of the same source code is possible without error. However, upgrading without rebuilding is not possible.

**To Reproduce**
Steps to reproduce the behavior:
1. Create an exe depending on CommandLineParser 2.8.0 that uses `VerbAttribute`
2. Replace CommandLineParser 2.8.0 with CommandLineParser 2.9.1 in the bin folder
3. Execute the exe
4. See error

**Additional context**
When having multiple exes in the same folder, all exes need to be rebuilt and updated simultaneously along with updating CommandLineParser in order to upgrade.

Reintroducing the 2.8.0 `VerbAttribute` constructor, (and possibly labeling it as obsolete), would allow assemblies built with version 2.8.0 and assemblies built with version 2.9.1 to both work with the new version (possibly requiring binding redirects).

Comece localizando o construtor de VerbAttribute no projeto C# e reproduza a atualização relatada do CommandLineParser 2.8.0 para o 2.9.1 sem recompilar o executável. Verifique os testes existentes relacionados ao VerbAttribute ou à compatibilidade de assemblies e, em seguida, garanta que assemblies compilados com ambas as versões possam ser executados com o pacote mais recente sem o erro de construtor relatado.

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