Back missing platform

commit_hash:b64c242188e3f161b10244acb7177f61addd771a

build/ya.conf.json

@@ -985,6 +985,16 @@
                         "os": "LINUX"
                     }
                 },
+                {
+                    "default": false,
+                    "host": {
+                        "os": "LINUX"
+                    },
+                    "target": {
+                        "arch": "wasm32",
+                        "os": "EMSCRIPTEN"
+                    }
+                },
                 {
                     "default": false,
                     "host": {