[material theme] Fix cm-error style
[material theme] Fix cm-error style

it seems `.cm-error` lost some specificity in [this commit](https://github.com/codemirror/CodeMirror/commit/a7d443ec82c1806d24e25ad8014a4d8651409320#diff-33646e9ee4d04eedb98a991a636c2302L35) that causes the error state to have same color as the tag.

SidPresse/CodeMirror,mtaran-google/CodeMirror,alur/CodeMirror,bfrohs/CodeMirror,hccampos/CodeMirror,notepadqq/CodeMirror,INTELOGIE/CodeMirror,adobe/CodeMirror2,crazy4chrissi/CodeMirror,ThebingServices/CodeMirror,SidPresse/CodeMirror,Dominator008/CodeMirror,antimatter15/CodeMirror,bfrohs/CodeMirror,schanzer/CodeMirror,ashmind/CodeMirror,dperetti/CodeMirror,sourcelair/CodeMirror,thomasjm/CodeMirror,TDaglis/CodeMirror,crazy4chrissi/CodeMirror,InternetGuru/CodeMirror,mizchi/CodeMirror,codio/CodeMirror,nightwing/CodeMirror,notepadqq/CodeMirror,Jisuanke/CodeMirror,rrandom/CodeMirror,alur/CodeMirror,bfrohs/CodeMirror,mihailik/CodeMirror,antimatter15/CodeMirror,jkaplon/CodeMirror,INTELOGIE/CodeMirror,thomasjm/CodeMirror,agendor/CodeMirror,crazy4chrissi/CodeMirror,INTELOGIE/CodeMirror,xeronith/CodeMirror,ficristo/CodeMirror,hccampos/CodeMirror,hackmdio/CodeMirror,alur/CodeMirror,antimatter15/CodeMirror,mtaran-google/CodeMirror,dperetti/CodeMirror,hackmdio/CodeMirror,ashmind/CodeMirror,rrandom/CodeMirror,jayaprabhakar/CodeMirror,Dominator008/CodeMirror,wingify/CodeMirror,Jisuanke/CodeMirror,schanzer/CodeMirror,jessegrosjean/CodeMirror,ejgallego/CodeMirror,jessegrosjean/CodeMirror,adobe/CodeMirror2,jkaplon/CodeMirror,kerabromsmu/CodeMirror,adobe/CodeMirror2,mizchi/CodeMirror,schanzer/CodeMirror,mizchi/CodeMirror,ZombieHippie/CodeMirror,MarcelGerber/CodeMirror,ejgallego/CodeMirror,notepadqq/CodeMirror,TDaglis/CodeMirror,MarcelGerber/CodeMirror,sourcelair/CodeMirror,sourcelair/CodeMirror,InternetGuru/CodeMirror,kerabromsmu/CodeMirror,ashmind/CodeMirror,wingify/CodeMirror,thomasjm/CodeMirror,codio/CodeMirror,xeronith/CodeMirror,xeronith/CodeMirror,dperetti/CodeMirror,ThebingServices/CodeMirror,namin/CodeMirror,namin/CodeMirror,pabloferz/CodeMirror,ejgallego/CodeMirror,Jisuanke/CodeMirror,jkaplon/CodeMirror,InternetGuru/CodeMirror,namin/CodeMirror,jayaprabhakar/CodeMirror,agendor/CodeMirror,grzegorzmazur/CodeMirror,ZombieHippie/CodeMirror,wingify/CodeMirror,mtaran-google/CodeMirror,kerabromsmu/CodeMirror,vincentwoo/CodeMirror,jayaprabhakar/CodeMirror,grzegorzmazur/CodeMirror,hackmdio/CodeMirror,vincentwoo/CodeMirror,ficristo/CodeMirror,codio/CodeMirror,ThebingServices/CodeMirror,mihailik/CodeMirror,TDaglis/CodeMirror,ficristo/CodeMirror,agendor/CodeMirror,vincentwoo/CodeMirror,nightwing/CodeMirror,nightwing/CodeMirror,grzegorzmazur/CodeMirror,ZombieHippie/CodeMirror,rrandom/CodeMirror,pabloferz/CodeMirror,mihailik/CodeMirror,MarcelGerber/CodeMirror,jessegrosjean/CodeMirror,Dominator008/CodeMirror,hccampos/CodeMirror,pabloferz/CodeMirror,SidPresse/CodeMirror