Install uv before running tests

Author: chrismcg

.github/workflows/build.yml

@@ -1,4 +1,4 @@
-import { awscdk } from 'projen';
+import { awscdk, JsonPatch } from 'projen';
 import { JobPermission } from 'projen/lib/github/workflows-model';
 const project = new awscdk.AwsCdkConstructLibrary({
   author: 'Eoin Shanaghy',
@@ -29,6 +29,7 @@ const project = new awscdk.AwsCdkConstructLibrary({
   },
   eslint: false,
 });
+
 const biomeWorkflow = project.github?.addWorkflow('biome');
 biomeWorkflow?.on({
   pullRequest: {
@@ -62,5 +63,10 @@ biomeWorkflow?.addJobs({
   },
 });
 
+const buildWorkflow = project.tryFindObjectFile('.github/workflows/build.yml');
+if (buildWorkflow) {
+  buildWorkflow.patch(JsonPatch.add('/jobs/build/steps/0', {"name": "Install uv", "run": "pip install uv"}));
+}
+
 project.files;
 project.synth();