Bump uvloop from 0.15.2 to 0.15.3

Bumps [uvloop](https://github.com/MagicStack/uvloop) from 0.15.2 to 0.15.3.
- [Release notes](https://github.com/MagicStack/uvloop/releases)
- [Commits](MagicStack/uvloop@v0.15.2...v0.15.3)

---
updated-dependencies:
- dependency-name: uvloop
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

requirements.txt

@@ -5,4 +5,4 @@ keystoneauth1==4.3.1
 git+https://github.com/cscfi/swift-browser-ui.git
 certifi==2021.5.30 
 gunicorn>=20.0.1
-uvloop==0.15.2
+uvloop==0.15.3

setup.py

@@ -18,7 +18,7 @@
         "python-swiftclient==3.12.0",
         "keystoneauth1==4.3.1",
         "gunicorn>=20.0.1",
-        "uvloop==0.15.2",
+        "uvloop==0.15.3",
         "certifi==2021.5.30",
         "swift-browser-ui" "@ git+https://github.com/cscfi/swift-browser-ui.git",
     ],