Tiny typo (#3360)

Spotted when reading docs

Author: gregorgorjanc

docs/c-api.rst

@@ -41,7 +41,7 @@ the C-equivalent methods as the Python API wraps this API.
 
 The main area of difference is, unlike the Python API, the C API doesn't do any
 decoding, encoding or schema validation of :ref:`sec_metadata` fields,
-instead only handling the byte sting representation of the metadata. Metadata is therefore
+instead only handling the byte string representation of the metadata. Metadata is therefore
 never used directly by any tskit C API method, just stored.
 
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