pip: update tornado dependency

requirements.txt

@@ -833,18 +833,18 @@ tomlkit==0.12.5 \
 toolz==0.12.1 \
     --hash=sha256:d22731364c07d72eea0a0ad45bafb2c2937ab6fd38a3507bf55eae8744aa7d85 \
     --hash=sha256:ecca342664893f177a13dac0e6b41cbd8ac25a358e5f215316d43e2100224f4d
-tornado==6.4 \
-    --hash=sha256:02ccefc7d8211e5a7f9e8bc3f9e5b0ad6262ba2fbb683a6443ecc804e5224ce0 \
-    --hash=sha256:10aeaa8006333433da48dec9fe417877f8bcc21f48dda8d661ae79da357b2a63 \
-    --hash=sha256:27787de946a9cffd63ce5814c33f734c627a87072ec7eed71f7fc4417bb16263 \
-    --hash=sha256:6f8a6c77900f5ae93d8b4ae1196472d0ccc2775cc1dfdc9e7727889145c45052 \
-    --hash=sha256:71ddfc23a0e03ef2df1c1397d859868d158c8276a0603b96cf86892bff58149f \
-    --hash=sha256:72291fa6e6bc84e626589f1c29d90a5a6d593ef5ae68052ee2ef000dfd273dee \
-    --hash=sha256:88b84956273fbd73420e6d4b8d5ccbe913c65d31351b4c004ae362eba06e1f78 \
-    --hash=sha256:e43bc2e5370a6a8e413e1e1cd0c91bedc5bd62a74a532371042a18ef19e10579 \
-    --hash=sha256:f0251554cdd50b4b44362f73ad5ba7126fc5b2c2895cc62b14a1c2d7ea32f212 \
-    --hash=sha256:f7894c581ecdcf91666a0912f18ce5e757213999e183ebfc2c3fdbf4d5bd764e \
-    --hash=sha256:fd03192e287fbd0899dd8f81c6fb9cbbc69194d2074b38f384cb6fa72b80e9c2
+tornado==6.4.1 \
+    --hash=sha256:163b0aafc8e23d8cdc3c9dfb24c5368af84a81e3364745ccb4427669bf84aec8 \
+    --hash=sha256:25486eb223babe3eed4b8aecbac33b37e3dd6d776bc730ca14e1bf93888b979f \
+    --hash=sha256:454db8a7ecfcf2ff6042dde58404164d969b6f5d58b926da15e6b23817950fc4 \
+    --hash=sha256:613bf4ddf5c7a95509218b149b555621497a6cc0d46ac341b30bd9ec19eac7f3 \
+    --hash=sha256:6d5ce3437e18a2b66fbadb183c1d3364fb03f2be71299e7d10dbeeb69f4b2a14 \
+    --hash=sha256:8ae50a504a740365267b2a8d1a90c9fbc86b780a39170feca9bcc1787ff80842 \
+    --hash=sha256:92d3ab53183d8c50f8204a51e6f91d18a15d5ef261e84d452800d4ff6fc504e9 \
+    --hash=sha256:a02a08cc7a9314b006f653ce40483b9b3c12cda222d6a46d4ac63bb6c9057698 \
+    --hash=sha256:b24b8982ed444378d7f21d563f4180a2de31ced9d8d84443907a0a64da2072e7 \
+    --hash=sha256:d9a566c40b89757c9aa8e6f032bcdb8ca8795d7c1a9762910c722b1635c9de4d \
+    --hash=sha256:e2e20b9113cd7293f164dc46fffb13535266e713cdb87bd2d15ddb336e96cfc4
 traitlets==5.14.3 \
     --hash=sha256:9ed0579d3502c94b4b3732ac120375cda96f923114522847de4b3bb98b96b6b7 \
     --hash=sha256:b74e89e397b1ed28cc831db7aea759ba6640cb3de13090ca145426688ff1ac4f