Fix typo in media pipeline docs
Fix typo in media pipeline docs

Ryezhang/scrapy,redapple/scrapy,pablohoffman/scrapy,shaform/scrapy,pawelmhm/scrapy,ArturGaspar/scrapy,Parlin-Galanodel/scrapy,wenyu1001/scrapy,rolando-contrib/scrapy,shaform/scrapy,finfish/scrapy,kmike/scrapy,arush0311/scrapy,scrapy/scrapy,rolando/scrapy,rolando-contrib/scrapy,rolando-contrib/scrapy,ssteo/scrapy,elacuesta/scrapy,wujuguang/scrapy,wenyu1001/scrapy,ssteo/scrapy,ssteo/scrapy,w495/scrapy,crasker/scrapy,pablohoffman/scrapy,pablohoffman/scrapy,taito/scrapy,elacuesta/scrapy,kmike/scrapy,foromer4/scrapy,eLRuLL/scrapy,taito/scrapy,darkrho/scrapy-scrapy,rootAvish/scrapy,rolando/scrapy,umrashrf/scrapy,darkrho/scrapy-scrapy,umrashrf/scrapy,shaform/scrapy,Ryezhang/scrapy,w495/scrapy,wujuguang/scrapy,rolando/scrapy,umrashrf/scrapy,foromer4/scrapy,Parlin-Galanodel/scrapy,taito/scrapy,redapple/scrapy,elacuesta/scrapy,foromer4/scrapy,starrify/scrapy,scrapy/scrapy,rootAvish/scrapy,kmike/scrapy,eLRuLL/scrapy,redapple/scrapy,ArturGaspar/scrapy,pawelmhm/scrapy,crasker/scrapy,eLRuLL/scrapy,starrify/scrapy,ArturGaspar/scrapy,arush0311/scrapy,darkrho/scrapy-scrapy,rootAvish/scrapy,Parlin-Galanodel/scrapy,dangra/scrapy,scrapy/scrapy,w495/scrapy,dangra/scrapy,pawelmhm/scrapy,wujuguang/scrapy,arush0311/scrapy,finfish/scrapy,crasker/scrapy,dangra/scrapy,Ryezhang/scrapy,finfish/scrapy,starrify/scrapy,wenyu1001/scrapy