Bump github.com/apple/swift-log from 1.6.3 to 1.6.4

Bumps [github.com/apple/swift-log](https://github.com/apple/swift-log) from 1.6.3 to 1.6.4.
- [Release notes](https://github.com/apple/swift-log/releases)
- [Commits](https://github.com/apple/swift-log/compare/1.6.3...1.6.4)

---
updated-dependencies:
- dependency-name: github.com/apple/swift-log
  dependency-version: 1.6.4
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Package.resolved

@@ -6,8 +6,8 @@
       "kind" : "remoteSourceControl",
       "location" : "https://github.com/apple/swift-log",
       "state" : {
-        "revision" : "3d8596ed08bd13520157f0355e35caed215ffbfa",
-        "version" : "1.6.3"
+        "revision" : "ce592ae52f982c847a4efc0dd881cc9eb32d29f2",
+        "version" : "1.6.4"
       }
     }
   ],