Move example dependency on runners into a profile
Move example dependency on runners into a profile

Even an optional runtime dependency, such as from the examples
to a runner, does get pulled in for testing. This meant that
all the dependencies for all runners had to be resolvable in an
integration testing context. It is quite inconvient.

Explicitly excluding runners via flags such as `-pl !runners/spark`
does not work since it causes errors in dependency resolution.

This change adds a profile, active by default, that can be
explicitly disabled to avoid pulling in dependencies.

rangadi/beam,yk5/beam,chamikaramj/beam,rangadi/beam,manuzhang/incubator-beam,chamikaramj/beam,apache/beam,RyanSkraba/beam,wangyum/beam,lukecwik/incubator-beam,amitsela/incubator-beam,jbonofre/incubator-beam,sammcveety/incubator-beam,lukecwik/incubator-beam,chamikaramj/beam,RyanSkraba/beam,wangyum/beam,amitsela/beam,ravwojdyla/incubator-beam,jasonkuster/beam,apache/beam,jbonofre/incubator-beam,apache/beam,peihe/incubator-beam,staslev/incubator-beam,jbonofre/beam,eljefe6a/incubator-beam,chamikaramj/beam,peihe/incubator-beam,RyanSkraba/beam,jbonofre/beam,charlesccychen/incubator-beam,sammcveety/incubator-beam,jasonkuster/incubator-beam,robertwb/incubator-beam,lukecwik/incubator-beam,rangadi/beam,RyanSkraba/beam,wtanaka/beam,manuzhang/beam,robertwb/incubator-beam,amitsela/beam,vikkyrk/incubator-beam,wangyum/beam,xsm110/Apache-Beam,charlesccychen/incubator-beam,xsm110/Apache-Beam,jbonofre/beam,yk5/beam,dhalperi/incubator-beam,jasonkuster/beam,eljefe6a/incubator-beam,markflyhigh/incubator-beam,chamikaramj/beam,jasonkuster/beam,apache/beam,dhalperi/beam,chamikaramj/incubator-beam,tgroh/beam,rangadi/beam,apache/beam,chamikaramj/beam,staslev/beam,yk5/beam,eljefe6a/incubator-beam,staslev/beam,amitsela/beam,robertwb/incubator-beam,RyanSkraba/beam,RyanSkraba/beam,charlesccychen/beam,charlesccychen/beam,markflyhigh/incubator-beam,chamikaramj/beam,xsm110/Apache-Beam,robertwb/incubator-beam,ravwojdyla/incubator-beam,tgroh/beam,chamikaramj/beam,amitsela/incubator-beam,robertwb/incubator-beam,jbonofre/beam,manuzhang/beam,manuzhang/beam,rangadi/beam,mxm/incubator-beam,apache/beam,josauder/AOP_incubator_beam,charlesccychen/beam,markflyhigh/incubator-beam,rangadi/beam,jasonkuster/incubator-beam,chamikaramj/beam,charlesccychen/beam,dhalperi/beam,charlesccychen/beam,robertwb/incubator-beam,amarouni/incubator-beam,joshualitt/incubator-beam,apache/beam,lukecwik/incubator-beam,lukecwik/incubator-beam,staslev/incubator-beam,apache/beam,charlesccychen/beam,apache/beam,joshualitt/incubator-beam,markflyhigh/incubator-beam,markflyhigh/incubator-beam,apache/beam,robertwb/incubator-beam,robertwb/incubator-beam,dhalperi/beam,rangadi/incubator-beam,tgroh/beam,markflyhigh/incubator-beam,iemejia/incubator-beam,lukecwik/incubator-beam,lukecwik/incubator-beam,markflyhigh/incubator-beam,peihe/incubator-beam,sammcveety/incubator-beam,lukecwik/incubator-beam,rangadi/incubator-beam,lukecwik/incubator-beam,lukecwik/incubator-beam,RyanSkraba/beam,staslev/beam,robertwb/incubator-beam,tgroh/beam,charlesccychen/beam,dhalperi/incubator-beam,ravwojdyla/incubator-beam,rangadi/beam,vikkyrk/incubator-beam,wtanaka/beam,manuzhang/incubator-beam,chamikaramj/incubator-beam,wangyum/beam,josauder/AOP_incubator_beam,charlesccychen/incubator-beam,amarouni/incubator-beam,rangadi/incubator-beam,iemejia/incubator-beam,robertwb/incubator-beam,tgroh/incubator-beam,mxm/incubator-beam,vikkyrk/incubator-beam,chamikaramj/beam,wtanaka/beam,apache/beam,tgroh/incubator-beam