docs(misc): adjust Nx version number in pkg json mentions (#20698)

docs/shared/migration/adding-to-existing-project.md

@@ -46,7 +46,7 @@ This process adds `nx` to your `package.json` at the root of your workspace:
   ...
   "devDependencies": {
     ...
-    "nx": "15.3.0"
+    "nx": "17.2.0"
   }
 }
 ```
@@ -106,7 +106,7 @@ Here's an example of a `build` and `lint` script being wrapped by Nx:
   },
   "devDependencies": {
     ...
-    "nx": "15.3.0"
+    "nx": "17.2.0"
   }
 }
 ```

docs/shared/migration/adding-to-monorepo.md

@@ -42,7 +42,7 @@ This process adds `nx` to your `package.json` at the root of your workspace:
   ...
   "devDependencies": {
     ...
-    "nx": "15.3.0"
+    "nx": "17.2.0"
   }
 }
 ```

docs/shared/migration/from-turborepo.md

@@ -34,7 +34,7 @@ This process adds `nx` to your `package.json` at the root of your workspace:
   ...
   "devDependencies": {
     ...
-    "nx": "16.8.0"
+    "nx": "17.2.0"
   }
 }
 ```