fix(firebaseapphosting): update the API

#### firebaseapphosting:v1beta

The following keys were changed:
- schemas.Config.properties.env.description

#### firebaseapphosting:v1

The following keys were changed:
- schemas.Config.properties.env.description

Author: yoshi-automation

discovery/firebaseapphosting-v1.json

@@ -1106,7 +1106,7 @@
       }
     }
   },
-  "revision": "20251023",
+  "revision": "20251030",
   "rootUrl": "https://firebaseapphosting.googleapis.com/",
   "schemas": {
     "ArchiveSource": {
@@ -1455,7 +1455,7 @@
       "id": "Config",
       "properties": {
         "env": {
-          "description": "Optional. Environment variables for this build.",
+          "description": "Optional. Supplied environment variables for a specific build. Provided at Build creation time and immutable afterwards. This field is only applicable for Builds using a build image - (e.g., ContainerSource or ArchiveSource with locally_build_source) Attempts to set this for other build types will result in an error",
           "items": {
             "$ref": "EnvironmentVariable"
           },

discovery/firebaseapphosting-v1beta.json

@@ -1103,7 +1103,7 @@
       }
     }
   },
-  "revision": "20251023",
+  "revision": "20251030",
   "rootUrl": "https://firebaseapphosting.googleapis.com/",
   "schemas": {
     "ArchiveSource": {
@@ -1475,7 +1475,7 @@
       "id": "Config",
       "properties": {
         "env": {
-          "description": "Optional. Environment variables for this build.",
+          "description": "Optional. Supplied environment variables for a specific build. Provided at Build creation time and immutable afterwards. This field is only applicable for Builds using a build image - (e.g., ContainerSource or ArchiveSource with locally_build_source) Attempts to set this for other build types will result in an error",
           "items": {
             "$ref": "EnvironmentVariable"
           },

src/apis/firebaseapphosting/v1.ts

@@ -379,7 +379,7 @@ export namespace firebaseapphosting_v1 {
    */
   export interface Schema$Config {
     /**
-     * Optional. Environment variables for this build.
+     * Optional. Supplied environment variables for a specific build. Provided at Build creation time and immutable afterwards. This field is only applicable for Builds using a build image - (e.g., ContainerSource or ArchiveSource with locally_build_source) Attempts to set this for other build types will result in an error
      */
     env?: Schema$EnvironmentVariable[];
     /**

src/apis/firebaseapphosting/v1beta.ts

@@ -387,7 +387,7 @@ export namespace firebaseapphosting_v1beta {
    */
   export interface Schema$Config {
     /**
-     * Optional. Environment variables for this build.
+     * Optional. Supplied environment variables for a specific build. Provided at Build creation time and immutable afterwards. This field is only applicable for Builds using a build image - (e.g., ContainerSource or ArchiveSource with locally_build_source) Attempts to set this for other build types will result in an error
      */
     env?: Schema$EnvironmentVariable[];
     /**