fix(readme): locked composer to a proper version (#21338)
fix(readme): locked composer to a proper version (#21338)

* fix(readme): locked composer to a proper version
Without a version lock, users get current stable

* match docs

supergibbs/bootstrap,xt0rted/bootstrap,seanwu99/bootstrap,janseliger/bootstrap,SweetProcess/bootstrap,johnajacob/bootstrap,n054/bootstrap,tjkohli/bootstrap,vsn4ik/bootstrap,SweetProcess/bootstrap,xt0rted/bootstrap,tibo66/bootstrap,igoynawamreh/bootstrap,inway/bootstrap,SweetProcess/bootstrap,joblocal/bootstrap,Hemphill/bootstrap-docs,tibo66/bootstrap,davethegr8/bootstrap,xt0rted/bootstrap,hebbet/bootstrap,NCARB/bootstrap,NCARB/bootstrap,Hemphill/bootstrap-docs,nice-fungal/bootstrap,yuyokk/bootstrap,andresgalante/bootstrap,lemuelbarango/bootstrap,inway/bootstrap,fschumann1211/bootstrap,afuno/bootstrap,zalog/bootstrap,stanwmusic/bootstrap,slavanga/bootstrap,yuyokk/bootstrap,TheFridayInstitute/bootstrap,GerHobbelt/bootstrap,copperdesign/bootstrap,Scoutski/bootstrap,gijsbotje/bootstrap,Lyricalz/bootstrap,peterblazejewicz/bootstrap,NCARB/bootstrap,IdanCo/bootstrap,JumpLinkNetwork/bootstrap-backward,Delagen/bootstrap,lipis/bootstrap,jipexu/bootstrap,slavanga/bootstrap,m5o/bootstrap,GerHobbelt/bootstrap,bootstrapbrasil/bootstrap,lipis/bootstrap,Scoutski/bootstrap,fschumann1211/bootstrap,sealocal/bootstrap,lemuelbarango/bootstrap,kvlsrg/bootstrap,edanbarak/bootstrap,stanwmusic/bootstrap,edanbarak/bootstrap,igoynawamreh/bootstrap,sealocal/bootstrap,seanwu99/bootstrap,tagliala/bootstrap,peterblazejewicz/bootstrap,andresgalante/bootstrap,IdanCo/bootstrap,hebbet/bootstrap,afuno/bootstrap,realcrowd/bootstrap,gijsbotje/bootstrap,n054/bootstrap,NCARB/bootstrap,vsn4ik/bootstrap,Delagen/bootstrap,9-chirno/chirno,lipis/bootstrap,janseliger/bootstrap,afuno/bootstrap,Lyricalz/bootstrap,realcrowd/bootstrap,supergibbs/bootstrap,lemuelbarango/bootstrap,jipexu/bootstrap,afuno/bootstrap,tagliala/bootstrap,Lyricalz/bootstrap,m5o/bootstrap,bootstrapbrasil/bootstrap,9-chirno/chirno,hebbet/bootstrap,supergibbs/bootstrap,hebbet/bootstrap,JumpLinkNetwork/bootstrap-backward,lipis/bootstrap,zalog/bootstrap,davethegr8/bootstrap,edanbarak/bootstrap,n054/bootstrap,creativewebjp/bootstrap,gijsbotje/bootstrap,andresgalante/bootstrap,joblocal/bootstrap,Hemphill/bootstrap-docs,n054/bootstrap,stanwmusic/bootstrap,TheFridayInstitute/bootstrap,jipexu/bootstrap,fschumann1211/bootstrap,andresgalante/bootstrap,igoynawamreh/bootstrap,GerHobbelt/bootstrap,bardiharborow/bootstrap,JumpLinkNetwork/bootstrap-backward,Scoutski/bootstrap,lemuelbarango/bootstrap,janseliger/bootstrap,yuyokk/bootstrap,tjkohli/bootstrap,slavanga/bootstrap,joblocal/bootstrap,nice-fungal/bootstrap,gijsbotje/bootstrap,bardiharborow/bootstrap,tibo66/bootstrap,coliff/bootstrap,nice-fungal/bootstrap,yuyokk/bootstrap,seanwu99/bootstrap,davethegr8/bootstrap,sealocal/bootstrap,johnajacob/bootstrap,peterblazejewicz/bootstrap,SweetProcess/bootstrap,creativewebjp/bootstrap,joblocal/bootstrap,davethegr8/bootstrap,kvlsrg/bootstrap,igoynawamreh/bootstrap,fschumann1211/bootstrap,Delagen/bootstrap,xt0rted/bootstrap,edanbarak/bootstrap,Scoutski/bootstrap,johnajacob/bootstrap,Lyricalz/bootstrap,creativewebjp/bootstrap,bardiharborow/bootstrap,realcrowd/bootstrap,coliff/bootstrap,tagliala/bootstrap,twbs/bootstrap,JumpLinkNetwork/bootstrap-backward,slavanga/bootstrap,TheFridayInstitute/bootstrap,creativewebjp/bootstrap,vsn4ik/bootstrap,kvlsrg/bootstrap,bootstrapbrasil/bootstrap,vsn4ik/bootstrap,zalog/bootstrap,bardiharborow/bootstrap,twbs/bootstrap,inway/bootstrap,janseliger/bootstrap,seanwu99/bootstrap,stanwmusic/bootstrap,supergibbs/bootstrap,tibo66/bootstrap,IdanCo/bootstrap,copperdesign/bootstrap,copperdesign/bootstrap,TheFridayInstitute/bootstrap,copperdesign/bootstrap,sealocal/bootstrap,realcrowd/bootstrap,IdanCo/bootstrap,Hemphill/bootstrap-docs,9-chirno/chirno,9-chirno/chirno,Delagen/bootstrap,johnajacob/bootstrap,jipexu/bootstrap