Can't deploy app that references postgres url

[davidfowl]

Seems like we have an issue with the new uri reference expression format. Likely related to #12216

#pragma warning disable ASPIRECSHARPAPPS001 // Type is for evaluation purposes only and is subject to change or removal in future updates. Suppress this diagnostic to proceed.

#:package Aspire.Hosting.Azure.AppContainers@13.0.0-preview.1.25524.10
#:package Aspire.Hosting.PostgreSQL@13.0.0-preview.1.25524.10
#:sdk Aspire.AppHost.Sdk@13.0.0-preview.1.25524.10

var builder = DistributedApplication.CreateBuilder(args);

builder.AddAzureContainerAppEnvironment("env");

var pg = builder.AddPostgres("pg").AddDatabase("db");

builder.AddCSharpApp("app", "app.cs")
.WithEnvironment("PG_URL",pg.Resource.UriExpression);

builder.Build().Run();

[DEBUG]   Step 'deploy-compute-resources' failed: Invalid expression type for 'uri' encoding: 
System.Runtime.CompilerServices.FormattableStringFactory+ConcreteFormattableString
[DEBUG] Step e17b308c-ebfd-4886-9ed0-e0a9ac14092b: FAILED - pipeline-validation completed with errors
[01:41:09] [dbug] DotNetCliRunner: dotnet(42864) stdout: fail: Aspire.Hosting.DistributedApplicationRunner[0]
[01:41:09] [dbug] DotNetCliRunner: dotnet(42864) stdout:       Failed to publish the distributed application.
[01:41:09] [dbug] DotNetCliRunner: dotnet(42864) stdout:       System.InvalidOperationException: Step 'deploy-compute-resources' failed: Invalid expression type for  
'uri' encoding: System.Runtime.CompilerServices.FormattableStringFactory+ConcreteFormattableString
[01:41:09] [dbug] DotNetCliRunner: dotnet(42864) stdout:        ---> System.ArgumentException: Invalid expression type for 'uri' encoding: 
System.Runtime.CompilerServices.FormattableStringFactory+ConcreteFormattableString
[01:41:09] [dbug] DotNetCliRunner: dotnet(42864) stdout:          at Aspire.Hosting.Azure.Utils.BicepFormattingHelpers.FormatBicepExpression(Object val, String       
format) in /_/src/Shared/BicepFormattingHelpers.cs:line 27
[01:41:09] [dbug] DotNetCliRunner: dotnet(42864) stdout:          at Aspire.Hosting.Azure.BaseContainerAppContext.ProcessValue(Object value, SecretType secretType,   
Object parent) in /_/src/Aspire.Hosting.Azure.AppContainers/BaseContainerAppContext.cs:line 317
[01:41:09] [dbug] DotNetCliRunner: dotnet(42864) stdout:          at Aspire.Hosting.Azure.BaseContainerAppContext.ProcessValue(Object value, SecretType secretType,   
Object parent) in /_/src/Aspire.Hosting.Azure.AppContainers/BaseContainerAppContext.cs:line 308
[01:41:09] [dbug] DotNetCliRunner: dotnet(42864) stdout:          at 
Aspire.Hosting.Azure.BaseContainerAppContext.AddEnvironmentVariablesAndCommandLineArgs(ContainerAppContainer container, Func`1 getContainerAppConfigurationSecrets,   
BicepValue`1 containerAppIdentityId) in /_/src/Aspire.Hosting.Azure.AppContainers/BaseContainerAppContext.cs:line 382
[01:41:09] [dbug] DotNetCliRunner: dotnet(42864) stdout:          at Aspire.Hosting.Azure.ContainerAppContext.BuildContainerApp(AzureResourceInfrastructure infra) in 
/_/src/Aspire.Hosting.Azure.AppContainers/ContainerAppContext.cs:line 81
[01:41:09] [dbug] DotNetCliRunner: dotnet(42864) stdout:          at Aspire.Hosting.Azure.AzureProvisioningResource.GetBicepTemplateFile(String directory, Boolean    
deleteTemporaryFileOnDispose) in /_/src/Aspire.Hosting.Azure/AzureProvisioningResource.cs:line 79
[01:41:09] [dbug] DotNetCliRunner: dotnet(42864) stdout:          at Aspire.Hosting.Azure.Provisioning.BicepProvisioner.GetOrCreateResourceAsync(AzureBicepResource   
resource, ProvisioningContext context, CancellationToken cancellationToken) in /_/src/Aspire.Hosting.Azure/Provisioning/Provisioners/BicepProvisioner.cs:line 134     
[01:41:09] [dbug] DotNetCliRunner: dotnet(42864) stdout:          at 
Aspire.Hosting.Azure.AzureEnvironmentResource.<>c__DisplayClass25_0.<<DeployComputeResourcesAsync>b__0>d.MoveNext() in 
/_/src/Aspire.Hosting.Azure/AzureEnvironmentResource.cs:line 336
[01:41:09] [dbug] DotNetCliRunner: dotnet(42864) stdout:       --- End of stack trace from previous location ---
[01:41:09] [dbug] DotNetCliRunner: dotnet(42864) stdout:          at 
Aspire.Hosting.Azure.AzureEnvironmentResource.<>c__DisplayClass25_0.<<DeployComputeResourcesAsync>b__0>d.MoveNext() in 
/_/src/Aspire.Hosting.Azure/AzureEnvironmentResource.cs:line 381
[01:41:09] [dbug] DotNetCliRunner: dotnet(42864) stdout:       --- End of stack trace from previous location ---
[01:41:09] [dbug] DotNetCliRunner: dotnet(42864) stdout:          at 
Aspire.Hosting.Azure.AzureEnvironmentResource.<>c__DisplayClass25_0.<<DeployComputeResourcesAsync>b__0>d.MoveNext() in 
/_/src/Aspire.Hosting.Azure/AzureEnvironmentResource.cs:line 381
[01:41:09] [dbug] DotNetCliRunner: dotnet(42864) stdout:       --- End of