Travis: Temporarily disable macOS builds
Travis: Temporarily disable macOS builds

Travis CI has had trouble the past few days and macOS builds error out
for no reason.

ZuBsPaCe/godot,DmitriySalnikov/godot,sanikoyes/godot,firefly2442/godot,Faless/godot,MarianoGnu/godot,sanikoyes/godot,pkowal1982/godot,ZuBsPaCe/godot,Paulloz/godot,akien-mga/godot,Shockblast/godot,MarianoGnu/godot,guilhermefelipecgs/godot,firefly2442/godot,honix/godot,firefly2442/godot,ZuBsPaCe/godot,DmitriySalnikov/godot,honix/godot,Valentactive/godot,ZuBsPaCe/godot,pkowal1982/godot,sanikoyes/godot,josempans/godot,Shockblast/godot,akien-mga/godot,BastiaanOlij/godot,Faless/godot,vkbsb/godot,josempans/godot,Zylann/godot,vnen/godot,honix/godot,Valentactive/godot,Valentactive/godot,MarianoGnu/godot,josempans/godot,josempans/godot,honix/godot,MarianoGnu/godot,Zylann/godot,guilhermefelipecgs/godot,godotengine/godot,DmitriySalnikov/godot,vnen/godot,firefly2442/godot,akien-mga/godot,MarianoGnu/godot,MarianoGnu/godot,BastiaanOlij/godot,godotengine/godot,Paulloz/godot,pkowal1982/godot,honix/godot,vkbsb/godot,MarianoGnu/godot,guilhermefelipecgs/godot,sanikoyes/godot,BastiaanOlij/godot,Faless/godot,BastiaanOlij/godot,pkowal1982/godot,Zylann/godot,Shockblast/godot,firefly2442/godot,akien-mga/godot,akien-mga/godot,akien-mga/godot,guilhermefelipecgs/godot,Faless/godot,sanikoyes/godot,guilhermefelipecgs/godot,sanikoyes/godot,akien-mga/godot,Paulloz/godot,ZuBsPaCe/godot,guilhermefelipecgs/godot,Shockblast/godot,vnen/godot,Valentactive/godot,vkbsb/godot,Zylann/godot,Faless/godot,DmitriySalnikov/godot,Valentactive/godot,Shockblast/godot,vnen/godot,Shockblast/godot,Zylann/godot,pkowal1982/godot,firefly2442/godot,vkbsb/godot,guilhermefelipecgs/godot,Zylann/godot,Faless/godot,godotengine/godot,vkbsb/godot,ZuBsPaCe/godot,Valentactive/godot,vnen/godot,pkowal1982/godot,godotengine/godot,Valentactive/godot,josempans/godot,Zylann/godot,Paulloz/godot,pkowal1982/godot,BastiaanOlij/godot,BastiaanOlij/godot,josempans/godot,godotengine/godot,vkbsb/godot,Shockblast/godot,DmitriySalnikov/godot,godotengine/godot,BastiaanOlij/godot,vkbsb/godot,guilhermefelipecgs/godot,Faless/godot,Zylann/godot,ZuBsPaCe/godot,Shockblast/godot,Paulloz/godot,akien-mga/godot,Paulloz/godot,firefly2442/godot,pkowal1982/godot,vnen/godot,DmitriySalnikov/godot,josempans/godot,honix/godot,Paulloz/godot,sanikoyes/godot,firefly2442/godot,godotengine/godot,MarianoGnu/godot,godotengine/godot,vnen/godot,DmitriySalnikov/godot,BastiaanOlij/godot,Valentactive/godot,josempans/godot,ZuBsPaCe/godot,Faless/godot,vnen/godot,vkbsb/godot,sanikoyes/godot