fix: yarnv4 requires shebangs in shell scripts to allow execution

.dockerignore

@@ -14,3 +14,4 @@ frontend/node_modules
 !.yarn/**
 !.yarnrc.yml
 !frontend/.yarn/**
+node_modules

frontend/.yarnrc.yml

@@ -1 +1,2 @@
 yarnPath: .yarn/releases/yarn-4.2.2.cjs
+nodeLinker: node-modules

frontend/check-imports.rc

@@ -1,3 +1,4 @@
+#!/usr/bin/env sh
 if grep -R --include="*.js" --include="*.jsx" --include="*.ts" --include="*.tsx" "from '@mui/icons-material'" src; then
   echo "Prohibited import from '@mui/icons-material' found. Use default imports referencing the file instead of the 
   global package. Example: import Delete from '@mui/icons-material/Delete';'"

frontend/src/component/feature/FeatureStrategy/FeatureStrategyCreate/FeatureStrategyCreate.test.tsx

@@ -165,7 +165,7 @@ describe('NewFeatureStrategyCreate', () => {
 
         expect(screen.getByText(expectedSegmentName)).toBeInTheDocument();
         expect(screen.getByText(expectedConstraintValue)).toBeInTheDocument();
-    });
+    }, 10000);
 
     test('should change variants settings', async () => {
         const { expectedVariantName } = setupComponent();