Bump to version 2.2.0

[TonyCTHsu]

Added

• Tracing: Add Rails Runner instrumentation (Rails Runner instrumentation #2509)
• Tracing: Introduce a new, reworked GraphQL tracer to comply with span attributes specification (Add new GraphQL tracer complying to span attributes specification #3672)
• Tracing: Enhance ActiveSupport::Cache instrumentation with ActiveSupport::Notifications subscription (Use ActiveSupport events to instrument ActiveSupport::Cache #3772)
• Profiling: Track unscaled allocation counts in allocation profiler ([PROF-10125] Track unscaled allocation counts in allocation profiler #3770)

Changed

• Core: Send Telemetry events in batches ([SDTEST-409] Send telemetry events in batches #3749)
• Tracing: Populate spans from ActiveSupport::Notifications as early as possible (Populate ActiveSupport Notification spans as early as possible  #3725)
• Profiling: Upgrade to libdatadog 10 ([PROF-10099] Upgrade to libdatadog 10 #3753)
• Profiling: Optimize CodeProvenance#record_loaded_files to avoid allocations ([NO-TICKET] Optimize CodeProvenance#record_loaded_files to avoid allocations #3757)

Fixed

• Core: Fix Telemetry events blocking main thread ([SDTEST-409] Send telemetry events in background thread to remove blocking HTTP calls from critical path #3718)
• Core: Fix deadlock from Telemetry threads ([SDTEST-409] fix deadlock issue: don't flush_events in main thread when calling stop, override #work_pending? instead #3743)
• Tracing: Fix empty log correlation when tracing is disabled (Return empty log correlation when tracing is disabled #3731)
• Tracing: Fix HTTP propagation when missing parent span id (HTTP propagator: Better handling of invalid data #3730)
• Tracing: Ensure _dd.p.tid tag with fixed size (Ensure the _dd.p.tid tag has fixed size #3729)
• OTel: Fix ids encoding/decoding for propagation (fix: ensure the correct ids are serialized and propagated #3709)
• Profiling: Workaround Ruby Dir returning incorrect results ([PROF-9342] Introduce profiler workaround for Ruby Dir interruption bug #3720)
• Profiling: Fix Phusion Passenger detection when missing from Gemfile/gems.rb ([PROF-10015] Fix Phusion Passenger detection when not in Gemfile/gems.rb #3750)
• Profiling: Fix rpath for linking to libdatadog when loading extension ([PROF-9926] Fix rpath for linking to libdatadog when loading from extension dir (cherry-pick from 1.x-stable) #3706)
• Profiling: Fix incorrect code provenance due to broken JSON monkey patch ([PROF-9821] Fix incorrect code provenance due to broken JSON monkey patch #3695)
• Profiling: Fix aggregation of actionview template classes ([PROF-10112] Simplify method names from actionview templates in profiler #3759, [PROF-10112] Also simplify actionview templates with three underscores #3774)