Use um instead of the special character until it is implemented upstream

lang/lang_en_ro.txt

@@ -384,7 +384,7 @@
 
 #MSG_BED_CORRECTION_FRONT c=14
 "Front side[um]"
-"Fata [\xe4m]"
+"Fata [um]"
 
 #MSG_SELFTEST_FANS c=20
 "Front/left fans"
@@ -512,7 +512,7 @@
 
 #MSG_BED_CORRECTION_LEFT c=14
 "Left side [um]"
-"Stanga [\xe4m]"
+"Stanga [um]"
 
 #MSG_LIN_CORRECTION c=18
 "Lin. correction"
@@ -876,7 +876,7 @@
 
 #MSG_BED_CORRECTION_REAR c=14
 "Rear side [um]"
-"Spate [\xe4m]"
+"Spate [um]"
 
 #MSG_UNLOAD_FILAMENT_REPEAT c=20 r=4
 "Please unload the filament first, then repeat this action."
@@ -912,7 +912,7 @@
 
 #MSG_BED_CORRECTION_RIGHT c=14
 "Right side[um]"
-"Dreapta [\xe4m]"
+"Dreapta [um]"
 
 #MSG_RPI_PORT c=13
 "RPi port"