#271: Update version of Poetry used

- Hopefully this will fix the `'Link' object has no attribute 'is_absolute'` error seen on GitHub Actions when installing the API's dependencies

.github/workflows/ci-build.yml

@@ -75,7 +75,7 @@ jobs:
     - name: Install Nox
       run: pip install nox==2020.8.22
     - name: Install Poetry
-      run: pip install poetry==1.1.4
+      run: pip install poetry==1.1.9
     - name: Install dependencies
       run: poetry install
 
@@ -105,7 +105,7 @@ jobs:
     - name: Install Nox
       run: pip install nox==2020.8.22
     - name: Install Poetry
-      run: pip install poetry==1.1.4
+      run: pip install poetry==1.1.9
 
     - name: Run Nox lint session
       run: nox -s lint
@@ -125,7 +125,7 @@ jobs:
     - name: Install Nox
       run: pip install nox==2020.8.22
     - name: Install Poetry
-      run: pip install poetry==1.1.4
+      run: pip install poetry==1.1.9
 
     - name: Run Nox black session
       run: nox -s black
@@ -145,7 +145,7 @@ jobs:
     - name: Install Nox
       run: pip install nox==2020.8.22
     - name: Install Poetry
-      run: pip install poetry==1.1.4
+      run: pip install poetry==1.1.9
 
     - name: Run Nox safety session
       run: nox -s safety
@@ -206,7 +206,7 @@ jobs:
       - name: Create config.json
         run: cp datagateway_api/config.json.example datagateway_api/config.json
       - name: Install Poetry
-        run: pip install poetry==1.1.4
+        run: pip install poetry==1.1.9
       - name: Install dependencies
         run: poetry install