Fix atests

Mainframe3270/keywords/read_write.py

@@ -39,7 +39,7 @@ def read_all_screen(self) -> str:
     def find_string(self, search_string: str, ignore_case: bool = False):
         """Returns a list of tuples of ypos and xpos for the position where the `search_string` was found,
         or an empty list if it was not found.
-        
+
         If `ignore_case` is set to `True`, then the search is done case-insensitively.
 
         Example:

atest/mainframe.robot

@@ -226,16 +226,12 @@ Test Send PF
     Page Should Contain String    Function key not allowed.
 
 Test Find String
-    ${position}    Find String    ${WELCOME}
+    ${position}    Find String    Welcome
     Should Be Equal    ${{ [(1, 10)] }}    ${position}
 
-Test Find String Multiple Times
-    ${position}    Find String    IBM
-    Should Be Equal    ${{ [(1, 46), (9, 16)] }}    ${position}
-
 Test Find String Case-Insensitive
-    ${position}    Find String    ibm    ignore_case=True
-    Should Be Equal    ${{ [(1, 46), (9, 16)] }}    ${position}
+    ${position}    Find String    Welcome    ignore_case=True
+    Should Be Equal    ${{ [(1, 10), (9, 5)] }}    ${position}
 
 Test Find String Without Result
     ${position}    Find String    ${STRING_NON_EXISTENT}