Bump tornado from 6.4.1 to 6.4.2 in /dev_tools/requirements/envs

Bumps [tornado](https://github.com/tornadoweb/tornado) from 6.4.1 to 6.4.2.
- [Changelog](https://github.com/tornadoweb/tornado/blob/v6.4.2/docs/releases.rst)
- [Commits](tornadoweb/tornado@v6.4.1...v6.4.2)

---
updated-dependencies:
- dependency-name: tornado
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

dev_tools/requirements/envs/dev.env.txt

@@ -696,7 +696,7 @@ tomlkit==0.13.2
     # via pylint
 toolz==1.0.0
     # via cytoolz
-tornado==6.4.1
+tornado==6.4.2
     # via
     #   ipykernel
     #   jupyter-client

dev_tools/requirements/envs/docs.env.txt

@@ -771,7 +771,7 @@ toolz==1.0.0
     # via
     #   -c envs/dev.env.txt
     #   cytoolz
-tornado==6.4.1
+tornado==6.4.2
     # via
     #   -c envs/dev.env.txt
     #   ipykernel

dev_tools/requirements/envs/format.env.txt

@@ -662,7 +662,7 @@ toolz==1.0.0
     # via
     #   -c envs/dev.env.txt
     #   cytoolz
-tornado==6.4.1
+tornado==6.4.2
     # via
     #   -c envs/dev.env.txt
     #   ipykernel

dev_tools/requirements/envs/pylint.env.txt

@@ -805,7 +805,7 @@ toolz==1.0.0
     # via
     #   -c envs/dev.env.txt
     #   cytoolz
-tornado==6.4.1
+tornado==6.4.2
     # via
     #   -c envs/dev.env.txt
     #   ipykernel

dev_tools/requirements/envs/pytest.env.txt

@@ -738,7 +738,7 @@ toolz==1.0.0
     # via
     #   -c envs/dev.env.txt
     #   cytoolz
-tornado==6.4.1
+tornado==6.4.2
     # via
     #   -c envs/dev.env.txt
     #   ipykernel

dev_tools/requirements/envs/runtime.env.txt

@@ -633,7 +633,7 @@ toolz==1.0.0
     # via
     #   -c envs/dev.env.txt
     #   cytoolz
-tornado==6.4.1
+tornado==6.4.2
     # via
     #   -c envs/dev.env.txt
     #   ipykernel