feat(logger): Support for external observability providers (#1511)

* Updated formatAttributes for additional parameters and LogItem return type

* Updated the unit tests to pass with new formatter

* Updated Powertool named objects to Powertools

* Updated tests to match new naming consistency

* Updated for tests for new naming consistency

* Updated formatter for new design decisions

* Update Logger for ephemeral attributes

* Update bringYourOwnFormatter documentation to match new formatter

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Co-authored-by: erikayao93 <erikayao@amazon.com>

packages/logger/src/formatter/PowertoolsLogFormatter.ts

@@ -16,7 +16,7 @@ class PowertoolsLogFormatter extends LogFormatter {
    *
    * @param {UnformattedAttributes} attributes
    * @param {LogAttributes} additionalLogAttributes
-   * @returns {LogItem}
+   * @returns {PowertoolsLog}
    */
   public formatAttributes(
     attributes: UnformattedAttributes,