Select the first project when searching in the project manager
Select the first project when searching in the project manager

This makes the project manager usable for opening existing projects
without ever touching the mouse. Just enter text in the autofocused
search box and press Enter.

This partially addresses #8149.

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