Use library_version instead of profiler_version

This seems to work fine, and it's a much better name.

Author: ivoanjo

lib/datadog/core/crashtracking/tag_builder.rb

@@ -25,7 +25,7 @@ def self.call(settings)
             'git.commit.sha' => Environment::Git.git_commit_sha,
             'is_crash' => 'true',
             'language' => 'ruby',
-            'profiler_version' => Core::Environment::Identity.gem_datadog_version,
+            'library_version' => Core::Environment::Identity.gem_datadog_version,
           }.compact
 
           # Make sure everything is an utf-8 string, to avoid encoding issues in downstream

spec/datadog/core/crashtracking/tag_builder_spec.rb

@@ -17,7 +17,7 @@
         'runtime_version' => RUBY_VERSION,
         'is_crash' => 'true',
         'language' => 'ruby',
-        'profiler_version' => Datadog::Core::Environment::Identity.gem_datadog_version,
+        'library_version' => Datadog::Core::Environment::Identity.gem_datadog_version,
       )
     end