Warning multiple modules with names that only differ in casing

It seems like a couple of icons are named equal being the unique difference the used casing. Babel is reporting us that:

```
./node_modules/remixicon-react/BookMarkFillIcon.js
There are multiple modules with names that only differ in casing.
This can lead to unexpected behavior when compiling on a filesystem with other case-semantic.
Use equal casing. Compare these module identifiers:
* /my-project/node_modules/react-scripts/node_modules/babel-loader/lib/index.js??ref--5-oneOf-3!/my-project/node_modules/remixicon-react/BookMarkFillIcon.js
Used by 1 module(s), i. e.
/my-project/node_modules/remixicon-react lazy /^\.\/.*Icon$/ groupOptions: {} namespace object
* /my-project/node_modules/react-scripts/node_modules/babel-loader/lib/index.js??ref--5-oneOf-3!/my-project/node_modules/remixicon-react/BookmarkFillIcon.js
Used by 1 module(s), i. e.
/my-project/node_modules/remixicon-react lazy /^\.\/.*Icon$/ groupOptions: {} namespace object

./node_modules/remixicon-react/BookMarkLineIcon.js
There are multiple modules with names that only differ in casing.
This can lead to unexpected behavior when compiling on a filesystem with other case-semantic.
Use equal casing. Compare these module identifiers:
* /my-project/node_modules/react-scripts/node_modules/babel-loader/lib/index.js??ref--5-oneOf-3!/my-project/node_modules/remixicon-react/BookMarkLineIcon.js
Used by 1 module(s), i. e.
/my-project/node_modules/remixicon-react lazy /^\.\/.*Icon$/ groupOptions: {} namespace object
* /my-project/node_modules/react-scripts/node_modules/babel-loader/lib/index.js??ref--5-oneOf-3!/my-project/node_modules/remixicon-react/BookmarkLineIcon.js
Used by 1 module(s), i. e.
/my-project/node_modules/remixicon-react lazy /^\.\/.*Icon$/ groupOptions: {} namespace object
```
I think we should cosider naming, and maybe start to use pascal-case to avoid this kind of problem with casing and OS.

Start by inspecting the conflicting files BookMarkFillIcon.js and BookmarkFillIcon.js, then BookMarkLineIcon.js and BookmarkLineIcon.js, and reproduce the Babel build warning shown in the issue. Determine the intended casing from the package’s existing icon names and verify that the build no longer reports modules differing only by case.

Written by the indexing model from the issue text.