Increase timeout for Clang toolchain build

Change-Id: I2c23567f279ac304044be7d5154db246d2e821dc
diff --git a/services/cr-buildbucket.cfg b/services/cr-buildbucket.cfg
index 061e7e8..aa3b3dc 100644
--- a/services/cr-buildbucket.cfg
+++ b/services/cr-buildbucket.cfg
@@ -552,6 +552,7 @@
         name: "clang_toolchain"
         properties: "manifest:toolchain"
       }
+      execution_timeout_secs: 7200  # 120 min
     }
 
     builders {
@@ -562,6 +563,7 @@
         name: "clang_toolchain"
         properties: "manifest:toolchain"
       }
+      execution_timeout_secs: 7200  # 120 min
     }
 
     builders {