CI add end-of-file-fixer
xref https://github.com/pandas-dev/pandas/pull/36600#issuecomment-702976850

> ok if you'd fix the EOF issue can merge (and yes good idea to add to the pre-commit hook / separate PR pls)

Note: in addition to adding the end-of-file-fixer pre-commit hook, I applied the following

```diff
diff --git a/scripts/generate_pip_deps_from_conda.py b/scripts/generate_pip_deps_from_conda.py
index c417f58f6..c6d00eb58 100755
--- a/scripts/generate_pip_deps_from_conda.py
+++ b/scripts/generate_pip_deps_from_conda.py
@@ -94,7 +94,7 @@ def main(conda_fname, pip_fname, compare=False):
         f"# This file is auto-generated from {fname}, do not modify.\n"
         "# See that file for comments about the need/usage of each dependency.\n\n"
     )
-    pip_content = header + "\n".join(pip_deps)
+    pip_content = header + "\n".join(pip_deps) + "\n"
 
     if compare:
         with open(pip_fname) as pip_fd:
```

----

I don't know how many of these we want to apply this to, for now I'm just excluding licenses (which I don't think should be touched?), html, txt, svg,and csv files