update global.json because dotnet docker image is updated with .NET 9…

… stable version now.

docker run --rm mcr.microsoft.com/dotnet/sdk:9.0 dotnet --info
.NET SDK:
 Version:           9.0.100
 Commit:            59db016f11
 Workload version:  9.0.100-manifests.3068a692
 MSBuild version:   17.12.7+5b8665660

The image info is: `Digest: sha256:7d24e90a392e88eb56093e4eb325ff883ad609382a55d42f17fd557b997022ca`.

Earlier today, the version was rc.2:

 docker run --rm mcr.microsoft.com/dotnet/sdk:9.0@sha256:c6a6d7995042bc8905825c2f1e2f8717733e90738a09fb0d30f917596f4bcb10 dotnet --info
.NET SDK:
 Version:           9.0.100-rc.2.24474.11
 Commit:            315e1305db
 Workload version:  9.0.100-manifests.cea95dba
 MSBuild version:   17.12.0-preview-24473-03+fea15fbd1

global.json

@@ -1,6 +1,6 @@
 {
   "sdk": {
     "rollForward": "latestFeature",
-    "version": "9.0.100-rc.2"
+    "version": "9.0.100"
   }
 }