GEODE-10465: Fix RAT failures by adding missing **/bin/** exclusion pattern (#7939)

This commit addresses RAT (Release Audit Tool) failures that occur when IDE-generated
bin/ directories are present in the workspace. The issue was caused by a missing
exclusion pattern that should have been included during the build system refactoring
in May 2022.

Root Cause Analysis:
- In April 2017, **/bin/** exclusion was added to RAT configuration (commit 4a09e88)
- Later removed due to legitimate bin/ folders in source tree (commit 39c72b2)
- During May 2022 build system refactoring (commit 509c0c6), the RAT configuration
  was moved from gradle/rat.gradle to build-tools/scripts/src/main/groovy/geode-rat.gradle
- The **/bin/** exclusion pattern was inadvertently omitted from the new configuration

Problem:
- IDEs (Eclipse, IntelliJ) generate bin/ directories containing compiled classes,
  test resources, and other build artifacts
- These files lack Apache license headers and cause RAT failures
- The .gitignore already excludes bin/ folders, indicating they are build artifacts

Solution:
- Add '**/bin/**' exclusion pattern to RAT configuration
- This prevents RAT from scanning IDE-generated build artifacts
- Consistent with existing exclusions for other build directories (**/build/**)
- Aligns with .gitignore patterns that already exclude bin/ folders

Testing:
- Verified RAT passes with and without bin/ directories present
- Confirmed exclusion works for files without license headers in bin/ folders
- No impact on legitimate source files that require license headers

This fix prevents future RAT failures for developers using IDEs that generate
bin/ directories during normal development workflow.

Author: sboorlagadda

build-tools/scripts/src/main/groovy/geode-rat.gradle

@@ -40,6 +40,7 @@ rat {
     'wrapper/**',
     '**/build/**',
     '**/build-*/**',
+    '**/bin/**',
     '.buildinfo',
     '**/release-features.rendered', // just for jenkins