fix typo in single mutation column name

pyrat-data-single-mutation.csv

@@ -1,4 +1,4 @@
-ID,Line / Strain (Name),DOB,Father,Mother,Sacrifice reason,Mutation 1,Grade 1,Mutation 2,Grade 2,Mutation 3,Grade 3,Father: Mutation 1, Father: Grade 1,Father: Mutation 2,Father: Grade 2,Father: Mutation 3,Father: Grade 3,Mother: Mutation 1,Mother: Grade 1,Mother: Mutation 2,Mother: Grade 2,Mother: Mutation 3,Mother: Grade 3
+ID,Line / Strain (Name),DOB,Father,Mother,Sacrifice reason,Mutation 1,Grade 1,Mutation 2,Grade 2,Mutation 3,Grade 3,Father: Mutation 1,Father: Grade 1,Father: Mutation 2,Father: Grade 2,Father: Mutation 3,Father: Grade 3,Mother: Mutation 1,Mother: Grade 1,Mother: Mutation 2,Mother: Grade 2,Mother: Mutation 3,Mother: Grade 3
 ID-001,Line-A,15/12/2025,ID-F1,ID-M1,End of experiment,Mut-A,het,,,,,Mut-A,wt,,,,,Mut-A,het,,,,,
 ID-002,Line-A,13/12/2025,ID-F1,ID-M1,End of experiment,Mut-A,wt,,,,,Mut-A,wt,,,,,Mut-A,het,,,,,
 ID-003,Line-A,11/12/2025,ID-F1,ID-M2,End of experiment,Mut-A,het,,,,,Mut-A,wt,,,,,Mut-A,het,,,,,