Update jinja2 to fix deprecation warnings on building website (#2711)

docs/Pipfile

@@ -6,7 +6,7 @@ verify_ssl = true
 [dev-packages]
 
 [packages]
-jinja2 = "==3.0.2" # FIXME: stop using deprecated features
+jinja2 = "*"
 pyyaml = "*"
 markdown = "*"
 lxml = "*"

docs/Pipfile.lock

@@ -1,7 +1,7 @@
 {
     "_meta": {
         "hash": {
-            "sha256": "3446f193e08e6a3c8f1d88af308dd7f8a668cccc270bc8374a4e95527f415a35"
+            "sha256": "16a9ef323592a417142c30be17e58c3cf36dc2bfdbf4757106a796b22262a1ce"
         },
         "pipfile-spec": 6,
         "requires": {},
@@ -16,11 +16,11 @@
     "default": {
         "jinja2": {
             "hashes": [
-                "sha256:827a0e32839ab1600d4eb1c4c33ec5a8edfbc5cb42dafa13b81f182f97784b45",
-                "sha256:8569982d3f0889eed11dd620c706d39b60c36d6d25843961f33f77fb6bc6b20c"
+                "sha256:31351a702a408a9e7595a8fc6150fc3f43bb6bf7e319770cbc0db9df9437e852",
+                "sha256:6088930bfe239f0e6710546ab9c19c9ef35e29792895fed6e6e31a023a182a61"
             ],
             "index": "pypi",
-            "version": "==3.0.2"
+            "version": "==3.1.2"
         },
         "lxml": {
             "hashes": [

docs/build_website.py

@@ -1,8 +1,9 @@
 #!/usr/bin/env python3
 import glob
 import itertools
-from jinja2 import Environment, FileSystemLoader, Markup, select_autoescape, contextfunction
+from jinja2 import Environment, FileSystemLoader, select_autoescape, pass_context
 from markdown import markdown
+from markupsafe import Markup
 import os
 import os.path
 import re
@@ -26,7 +27,7 @@ env.filters['entry_id'] = lambda input: re.sub(r"[ `]", '', input)
 env.filters['markdownify'] = lambda input: Markup(markdown(input))
 env.filters['no_paragraph'] = lambda input: Markup(re.sub(r"</?p>", '', input))
 
-env.globals['unique_id'] = contextfunction(
+env.globals['unique_id'] = pass_context(
     lambda ctx: str(next(ctx['unique_ctr'])))
 
 env.globals.update(load_yml_file('site.yml'))