fix: AVM-RES: Update preferredRoutingGateway and virtualRouterAsn (#6266)

- Changed preferredRoutingGateway from 'None' to 'ExpressRoute'
- Updated virtualRouterAsn from 100 to 65515
- Adjusted test cases to reflect the new parameter values

## Description

Fixes #6264 

## Pipeline Reference

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## Type of Change

<!-- Use the checkboxes [x] on the options that are relevant. -->

- Azure Verified Module updates:
- [X] Bugfix containing backwards-compatible bug fixes, and I have NOT
bumped the MAJOR or MINOR version in `version.json`:
- [ ] Feature update backwards compatible feature updates, and I have
bumped the MINOR version in `version.json`.
- [ ] Breaking changes and I have bumped the MAJOR version in
`version.json`.
  - [X] Update to documentation
- [ ] Update to CI Environment or utilities (Non-module affecting
changes)

## Checklist

- [X] I'm sure there are no other open Pull Requests for the same
update/change
- [X] I have run `Set-AVMModule` locally to generate the supporting
module files.
- [X] My corresponding pipelines / checks run clean and green without
any errors or warnings
- [ ] I have updated the module's CHANGELOG.md file with an entry for
the next version

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Author: arnoldna

avm/res/network/virtual-hub/README.md

@@ -164,15 +164,15 @@ module virtualHub 'br/public:avm/res/network/virtual-hub:<version>' = {
       kind: 'CanNotDelete'
       name: 'myCustomLockName'
     }
-    preferredRoutingGateway: 'None'
+    preferredRoutingGateway: 'ExpressRoute'
     routingIntent: {}
     sku: 'Standard'
     tags: {
       Environment: 'Non-Prod'
       'hidden-title': 'This is visible in the resource name'
       Role: 'DeploymentValidation'
     }
-    virtualRouterAsn: 100
+    virtualRouterAsn: 65515
     virtualRouterAutoScaleConfiguration: {
       minCount: 2
     }
@@ -259,7 +259,7 @@ module virtualHub 'br/public:avm/res/network/virtual-hub:<version>' = {
       }
     },
     "preferredRoutingGateway": {
-      "value": "None"
+      "value": "ExpressRoute"
     },
     "routingIntent": {
       "value": {}
@@ -275,7 +275,7 @@ module virtualHub 'br/public:avm/res/network/virtual-hub:<version>' = {
       }
     },
     "virtualRouterAsn": {
-      "value": 100
+      "value": 65515
     },
     "virtualRouterAutoScaleConfiguration": {
       "value": {
@@ -346,15 +346,15 @@ param lock = {
   kind: 'CanNotDelete'
   name: 'myCustomLockName'
 }
-param preferredRoutingGateway = 'None'
+param preferredRoutingGateway = 'ExpressRoute'
 param routingIntent = {}
 param sku = 'Standard'
 param tags = {
   Environment: 'Non-Prod'
   'hidden-title': 'This is visible in the resource name'
   Role: 'DeploymentValidation'
 }
-param virtualRouterAsn = 100
+param virtualRouterAsn = 65515
 param virtualRouterAutoScaleConfiguration = {
   minCount: 2
 }

avm/res/network/virtual-hub/tests/e2e/max/main.test.bicep

@@ -98,16 +98,14 @@ module testDeployment '../../../main.bicep' = [
           }
         }
       ]
-      sku:'Standard'
+      sku: 'Standard'
       virtualRouterAutoScaleConfiguration: {
         minCount: 2
       }
-      preferredRoutingGateway: 'None'
+      preferredRoutingGateway: 'ExpressRoute'
       hubRoutingPreference: 'ASPath'
-      virtualRouterAsn: 100
-      routingIntent: {
-
-      }
+      virtualRouterAsn: 65515
+      routingIntent: {}
       tags: {
         'hidden-title': 'This is visible in the resource name'
         Environment: 'Non-Prod'