fix: Correct Markdown format for Tracing link in README

[noid11]

Issue #, if available: fix markdown link format

Description of changes: fix Trancing link format

 ## Tracing and Logging
 
-The Rust Runtime for Lambda integrates with the (Tracing)[https://tracing.rs] libraries to provide tracing and logging.
+The Rust Runtime for Lambda integrates with the [Tracing](https://tracing.rs) libraries to provide tracing and logging.

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