Update net7 templates (#3262)

resources/backupTemplates/Microsoft.Azure.Functions.ExtensionBundle/version.txt

@@ -1 +1 @@
-2.13.0
+2.15.0

resources/backupTemplates/dotnet/~2/version.txt

@@ -1 +1 @@
-2.60.0
+2.60.1

resources/backupTemplates/dotnet/~4/version.txt

@@ -1 +1 @@
-4.18.1
+4.19.0

resources/backupTemplates/script/~2/version.txt

@@ -1 +1 @@
-2.60.0
+2.60.1

resources/backupTemplates/script/~4/version.txt

@@ -1 +1 @@
-4.18.1
+4.19.0

test/updateBackupTemplates.ts

@@ -34,6 +34,7 @@ suite('Backup templates', () => {
             { language: ProjectLanguage.CSharp, projectTemplateKey: 'net5.0-isolated', versions: [FuncVersion.v3, FuncVersion.v4] },
             { language: ProjectLanguage.CSharp, projectTemplateKey: 'net6.0', versions: [FuncVersion.v4] },
             { language: ProjectLanguage.CSharp, projectTemplateKey: 'net6.0-isolated', versions: [FuncVersion.v4] },
+            { language: ProjectLanguage.CSharp, projectTemplateKey: 'net7.0-isolated', versions: [FuncVersion.v4] },
             { language: ProjectLanguage.Java, versions: [FuncVersion.v2, FuncVersion.v3, FuncVersion.v4] }
         ];