Remove unneeded exec bits from some files

I noticed that some files in rubygems were executable, and I could think
of no reason why they should be.

In general, I think ruby files should never have the executable bit set
unless they include a shebang, so I run the following command over the
whole repo:

```bash
find . -name '*.rb' -type f -executable -exec bash -c 'grep -L "^#!" $1 || chmod -x $1' _ {} \;
```

5 files changed, 0 insertions, 0 deletions

diff --git a/test/csv/test_data_converters.rb b/test/csv/test_data_converters.rb
index 1620e077be..1620e077be 100755..100644
--- a/test/csv/test_data_converters.rb
+++ b/test/csv/test_data_converters.rb
diff --git a/test/csv/test_encodings.rb b/test/csv/test_encodings.rb
index acee03db45..acee03db45 100755..100644
--- a/test/csv/test_encodings.rb
+++ b/test/csv/test_encodings.rb
diff --git a/test/csv/test_features.rb b/test/csv/test_features.rb
index d6eb2dc13b..d6eb2dc13b 100755..100644
--- a/test/csv/test_features.rb
+++ b/test/csv/test_features.rb
diff --git a/test/csv/test_row.rb b/test/csv/test_row.rb
index f709dd3f13..f709dd3f13 100755..100644
--- a/test/csv/test_row.rb
+++ b/test/csv/test_row.rb
diff --git a/test/csv/test_table.rb b/test/csv/test_table.rb
index 50edc77e40..50edc77e40 100755..100644
--- a/test/csv/test_table.rb
+++ b/test/csv/test_table.rb