Remove if RUBY_VERSION from gemspec (#366)

* Remove `if RUBY_VERSION` from gemspec

The gemspec is evaluated during `rake release`, so the `if RUBY_VERSION`
condition does not depend on the user's Ruby version.
See: https://docs.rubocop.org/rubocop/cops_gemspec.html

* Updating config to allow tests to pass

---------

Co-authored-by: Kyle Burgess <kylemburgess03@gmail.com>

Author: a2ikm

.evergreen/config.yml

@@ -50,6 +50,7 @@ functions:
     # Make an evergreen exapanstion file with dynamic values
     - command: shell.exec
       params:
+        shell: bash
         working_dir: "src"
         script: |
            # Get the current unique version of this checkout

.evergreen/config/functions.yml.erb

@@ -15,6 +15,7 @@ functions:
     # Make an evergreen exapanstion file with dynamic values
     - command: shell.exec
       params:
+        shell: bash
         working_dir: "src"
         script: |
            # Get the current unique version of this checkout

bson.gemspec

@@ -34,11 +34,9 @@ Gem::Specification.new do |s|
     s.platform   = 'java'
   end
 
-  if RUBY_VERSION > '3.2.99'
-    s.add_dependency 'base64'
-    s.add_dependency 'bigdecimal'
-    s.add_dependency 'ostruct'
-  end
+  s.add_dependency 'base64'
+  s.add_dependency 'bigdecimal'
+  s.add_dependency 'ostruct'
 
   s.test_files = Dir.glob('spec/**/*')