chore(deps): update dockerfile and global.json updates to v9.0.309

Author: renovate[bot]

.devcontainer/Dockerfile

@@ -1,5 +1,5 @@
 # Refer to https://hub.docker.com/_/microsoft-dotnet-sdk for available versions
-FROM mcr.microsoft.com/dotnet/sdk:9.0.306-noble@sha256:d88e637d15248531967111fba05c6725ad45ea1dace3d35d8cfe2c4d4094e25d
+FROM mcr.microsoft.com/dotnet/sdk:9.0.309-noble@sha256:78807c5f4b1e80a9ea569b01e1a300eabc2403e636226bfff58df21c6aa0b5b5
 
 # Installing mono makes `dotnet test` work without errors even for net472.
 # But installing it takes a long time, so it's excluded by default.

global.json

@@ -1,6 +1,6 @@
 {
   "sdk": {
-    "version": "9.0.306",
+    "version": "9.0.309",
     "rollForward": "patch",
     "allowPrerelease": false
   }