provision/docker: remove the TSURU_APP_DIR env var
provision/docker: remove the TSURU_APP_DIR env var

There's the TSURU_APPDIR, and we don't use it.

cezarsa/tsuru,gwmoura/tsuru,gciotta/tsuru,cgvarela/tsuru,ggarnier/tsuru,kgrvamsi/tsuru,cgvarela/tsuru,tuxmonteiro/tsuru,hcxiong/tsuru,RichardKnop/tsuru,ggarnier/tsuru,ArxdSilva/tsuru,gciotta/tsuru,firebitsbr/tsuru,Endika/tsuru,mderaldo/tsuru,mderaldo/tsuru,jblancett/tsuru,gciotta/tsuru,tsuru/tsuru,cgvarela/tsuru,cezarsa/tsuru,jblancett/tsuru,Endika/tsuru,kgrvamsi/tsuru,RichardKnop/tsuru,Endika/tsuru,guilhermebr/tsuru,guilhermebr/tsuru,hcxiong/tsuru,ArxdSilva/tsuru,tsuru/tsuru,cezarsa/tsuru,hcxiong/tsuru,tsuru/tsuru,hugoantunes/tsuru,gwmoura/tsuru,jblancett/tsuru,ArxdSilva/tsuru,guilhermebr/tsuru,ggarnier/tsuru,mderaldo/tsuru,kgrvamsi/tsuru,hugoantunes/tsuru,ArxdSilva/tsuru,cezarsa/tsuru,ggarnier/tsuru,4eek/tsuru,4eek/tsuru,gwmoura/tsuru,tuxmonteiro/tsuru,RichardKnop/tsuru,firebitsbr/tsuru,firebitsbr/tsuru,tuxmonteiro/tsuru,guilhermebr/tsuru,tsuru/tsuru,4eek/tsuru