Fix broken filtering on documents page

Introduced in 35495e7. The reset link was also hardcoded for
the documents view.

app/general/tests/test_documents.py

@@ -40,3 +40,9 @@ def test_view_basics(self):
         self.assertEqual(response.status_code, 200)
         self.assertContains(response, 'id="main-heading"')
         self.assertIn("documents", response.context)
+
+    def test_with_filters(self):
+        response = self.client.get(reverse("documents"), {"language": self.language3.id})
+        self.assertEqual(response.status_code, 200)
+        self.assertEqual(len(response.context["documents"]), 1)
+        self.assertEqual(response.context["documents"][0]["document"].title, "Document 6")

app/templates/app/_subj_lang_institution_filter.html

@@ -1,6 +1,6 @@
 {% load i18n %}
 {% spaceless %}
-<form method="GET" action="" class="mb-3">
+<form method="GET" action="{% url view %}" class="mb-3">
     <div class="d-flex flex-wrap gap-2">
         <div class="form-group flex-fill mb-2">
             <label for="subject">{% trans "Subject" %}</label>
@@ -41,7 +41,7 @@
     </div>
     <div class="d-flex flex-wrap">
         <button type="submit" class="btn btn-primary mt-2 me-2">{% trans "Filter" %}</button>
-        <a href="{% url 'documents' %}" class="btn btn-secondary mt-2">{% trans "Reset" %}</a>
+        <a href="{% url view %}" class="btn btn-secondary mt-2">{% trans "Reset" %}</a>
     </div>
 </form>
 {% endspaceless %}

app/templates/app/documents.html

@@ -10,7 +10,7 @@
 <div class="text-break m-4">
     <h1 id="main-heading">{% trans "Documents" %}</h1>
 
-    {% include "app/_subj_lang_institution_filter.html" %}
+    {% include "app/_subj_lang_institution_filter.html" with view="documents"%}
 
     {% for item in documents %}
         <div class="mt-4">{# additional indent simplifies comparison with projects.html #}

app/templates/app/projects.html

@@ -10,7 +10,7 @@
 <div class="text-break m-4">
     <h1 id="main-heading">{% trans "Projects" %}</h1>
 
-    {% include "app/_subj_lang_institution_filter.html" %}
+    {% include "app/_subj_lang_institution_filter.html" with view="projects" %}
 
     {% for item in projects %}
     <div class="container-fluid mt-4 mb-5 p-0">{# container adds unwanted padding #}