Disable GitHub_15291.cmd for x86
Disable GitHub_15291.cmd for x86

It fails under MinOpts. Disable until it is fixed.

Tracked with #15566.

ruben-ayrapetyan/coreclr,yizhang82/coreclr,poizan42/coreclr,poizan42/coreclr,mmitche/coreclr,krk/coreclr,wtgodbe/coreclr,wtgodbe/coreclr,wtgodbe/coreclr,JosephTremoulet/coreclr,poizan42/coreclr,ruben-ayrapetyan/coreclr,cshung/coreclr,mmitche/coreclr,mmitche/coreclr,JosephTremoulet/coreclr,cshung/coreclr,krk/coreclr,mmitche/coreclr,ruben-ayrapetyan/coreclr,krk/coreclr,poizan42/coreclr,JosephTremoulet/coreclr,mmitche/coreclr,krk/coreclr,wtgodbe/coreclr,krk/coreclr,JosephTremoulet/coreclr,ruben-ayrapetyan/coreclr,cshung/coreclr,poizan42/coreclr,yizhang82/coreclr,ruben-ayrapetyan/coreclr,cshung/coreclr,yizhang82/coreclr,yizhang82/coreclr,krk/coreclr,ruben-ayrapetyan/coreclr,yizhang82/coreclr,JosephTremoulet/coreclr,cshung/coreclr,yizhang82/coreclr,wtgodbe/coreclr,JosephTremoulet/coreclr,cshung/coreclr,poizan42/coreclr,wtgodbe/coreclr,mmitche/coreclr