fix: use enum.StrEnum instead of str, enum.Enum (#14)

Fix ruff UP042 lint errors in SymbolBinding and SymbolType classes.

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Signed-off-by: Christian Heimes <cheimes@redhat.com>
Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

Author: tiran

src/elfdeps/_elfdeps.py

@@ -31,14 +31,14 @@
 )
 
 
-class SymbolBinding(str, enum.Enum):
+class SymbolBinding(enum.StrEnum):
     """ELF dynamic symbol binding (STB_*)"""
 
     GLOBAL = "global"  # Global symbol
     WEAK = "weak"  # Weak symbol
 
 
-class SymbolType(str, enum.Enum):
+class SymbolType(enum.StrEnum):
     """ELF dynamic symbol type (STT_*)"""
 
     NOTYPE = "notype"  # Symbol type is unspecified