pytest: Fix python tests involving RaveLoadPlugin

[undisputed-seraphim]

Due to the change in the way plugins are loaded in RaveLoadPlugins (https://github.com/rdiankov/openrave/pull/1137): File names must be non-truncated (myplugin -> libmyplugin.so).

Pipeline #486583

[rdiankov]

@undisputed-seraphim Just FYI, it looks like windows support is being dropped.

[undisputed-seraphim]

@undisputed-seraphim Just FYI, it looks like windows support is being dropped.

I can't tell if this is just a remark or if you'd like something to be changed :sweat_smile:

But yeah, openrave isn't buildable on Windows since I joined, but if you'd like that to change, I can make the necessary changes.

[rdiankov]

@undisputed-seraphim Not buildable on windows could just be a build problem. However, this change would make it incompatible from a design perspective, so at least we have to worry about that.

[rdiankov]

@undisputed-seraphim let's try to figure out a design that doesn't involve users knowing the prefix and extensions of the plugins

[undisputed-seraphim]

@rdiankov Okay, let me come up with another solution.

[cielavenir]

Why don't you simply add PLUGIN_EXT when loading?

[cielavenir]

@undisputed-seraphim By the way, after https://github.com/rdiankov/openrave/pull/1137 , OPENRAVE_PLUGINS='' has to be set explicitly, which does not seem good for plain openrave installation. /cc @lazydroid

[cielavenir]

Those two issue are addressed by https://github.com/rdiankov/openrave/pull/1227

[cielavenir]

will be replaced by #1227