fix: use absolute paths to ensure compatibility with v4 Compose

Author: czubocha

Diff for: lib/inject.js

@@ -153,15 +153,15 @@ async function injectAllRequirements(funcArtifact) {
           return this.options.zip
             ? func
             : injectRequirements(
-                path.join('.serverless', func.module, 'requirements'),
+                path.join(this.serverless.serviceDir, '.serverless', func.module, 'requirements'),
                 func.package.artifact,
                 injectionRelativePath,
                 this.options
               );
         });
     } else if (!this.options.zip) {
       await injectRequirements(
-        path.join('.serverless', 'requirements'),
+        path.join(this.serverless.serviceDir, '.serverless', 'requirements'),
         this.serverless.service.package.artifact || funcArtifact,
         injectionRelativePath,
         this.options