DX-120970 Fix macOS: remove brew pin cmake/boost

brew pin cmake fails on newer Homebrew (runner >=20260525) because it
resolves cmake via the API and hits the cmake cask instead of the
formula. brew bundle --file=arrow/cpp/Brewfile was already working
(cmake pre-installed on runner → "Using cmake"). The pins are not
needed in CI since no brew upgrade runs after the local tap install.

Author: akravchukdremio

dev/tasks/java-jars/github.yml

@@ -136,9 +136,7 @@ jobs:
           done
           brew install --overwrite python
 
-          # Newer Homebrew (runner >=20260525) resolves brew "cmake" to the cmake cask.
-          # Skip cmake/boost here; they are installed below with pinned versions.
-          HOMEBREW_BUNDLE_BREW_SKIP="cmake boost" brew bundle --file=arrow/cpp/Brewfile
+          brew bundle --file=arrow/cpp/Brewfile
           # We want to link aws-sdk-cpp statically but Homebrew's
           # aws-sdk-cpp provides only shared library. If we have
           # Homebrew's aws-sdk-cpp, our build mix Homebrew's
@@ -165,8 +163,6 @@ jobs:
           cp ./homebrew-custom/Formula/*.rb "$(brew --repo local/homebrew-custom)/Formula/"
           brew install -v local/homebrew-custom/cmake
           brew install -v local/homebrew-custom/boost
-          brew pin cmake
-          brew pin boost
           #