fix generate contract path and add alembic to dependencies

backend/requirements.txt

@@ -63,3 +63,4 @@ weasyprint==68.1
 webencodings==0.5.1
 websockets==16.0
 zopfli==0.4.1
+alembic==1.18.4

backend/src/contracts/generate_contract.py

@@ -15,7 +15,7 @@ def generate_html_contract(
     recurrent_price: float,
     total_price: float
 ):    
-    template_dir = pathlib.Path().resolve() + "/src/contracts/templates"
+    template_dir = pathlib.Path("./src/contracts/templates").resolve()
     template_loader = jinja2.FileSystemLoader(searchpath=template_dir)
     template_env = jinja2.Environment(loader=template_loader, autoescape=jinja2.select_autoescape(["html", "xml"]))
     template_file = "layout.html"