Update README.md

Co-authored-by: Pete Gadomski <pete.gadomski@gmail.com>

Author: Phil Varner

README.md

@@ -12,7 +12,7 @@ To install the classes in your local Python env, run:
 
 ```shell
 cd stac_fastapi/elasticsearch
-pip install -e .[dev]
+pip install -e '.[dev]'
 ```
 
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