update modelcluster/taggit in doc dependencies
update modelcluster/taggit in doc dependencies

timorieber/wagtail,wagtail/wagtail,Toshakins/wagtail,jnns/wagtail,jnns/wagtail,kaedroho/wagtail,thenewguy/wagtail,torchbox/wagtail,mixxorz/wagtail,Toshakins/wagtail,rsalmaso/wagtail,FlipperPA/wagtail,nimasmi/wagtail,wagtail/wagtail,zerolab/wagtail,timorieber/wagtail,kaedroho/wagtail,nimasmi/wagtail,gasman/wagtail,nealtodd/wagtail,nimasmi/wagtail,mixxorz/wagtail,nimasmi/wagtail,takeflight/wagtail,wagtail/wagtail,wagtail/wagtail,Toshakins/wagtail,takeflight/wagtail,mixxorz/wagtail,thenewguy/wagtail,gasman/wagtail,jnns/wagtail,zerolab/wagtail,gasman/wagtail,gasman/wagtail,gasman/wagtail,zerolab/wagtail,timorieber/wagtail,rsalmaso/wagtail,torchbox/wagtail,timorieber/wagtail,mixxorz/wagtail,nealtodd/wagtail,FlipperPA/wagtail,wagtail/wagtail,rsalmaso/wagtail,takeflight/wagtail,zerolab/wagtail,mixxorz/wagtail,iansprice/wagtail,kaedroho/wagtail,thenewguy/wagtail,rsalmaso/wagtail,iansprice/wagtail,nealtodd/wagtail,thenewguy/wagtail,nealtodd/wagtail,mikedingjan/wagtail,takeflight/wagtail,FlipperPA/wagtail,mikedingjan/wagtail,jnns/wagtail,mikedingjan/wagtail,FlipperPA/wagtail,rsalmaso/wagtail,iansprice/wagtail,torchbox/wagtail,iansprice/wagtail,kaedroho/wagtail,mikedingjan/wagtail,Toshakins/wagtail,kaedroho/wagtail,torchbox/wagtail,zerolab/wagtail,thenewguy/wagtail