FIX: Handle error bar empty theme object (#3046)

Author: masiddee

.changeset/afraid-donuts-tease.md

@@ -0,0 +1,5 @@
+---
+"victory-errorbar": patch
+---
+
+add default borderwidth value

package.json

@@ -455,4 +455,4 @@
       "node": ">=18.0.0"
     }
   }
-}
+}

packages/victory-errorbar/src/helper-methods.tsx

@@ -215,6 +215,7 @@ export const getBaseProps = (initialProps, fallbackProps) => {
       width,
     },
   };
+  const DEFAULT_BORDER_WIDTH = 8;
 
   return data.reduce((childProps, datum, index) => {
     const eventKey = !Helpers.isNil(datum.eventKey) ? datum.eventKey : index;
@@ -223,7 +224,7 @@ export const getBaseProps = (initialProps, fallbackProps) => {
     const errorX = getErrors(props, formattedDatum, "x");
     const errorY = getErrors(props, formattedDatum, "y");
     const dataProps = {
-      borderWidth,
+      borderWidth: borderWidth ? borderWidth : DEFAULT_BORDER_WIDTH,
       data,
       datum: formattedDatum,
       errorX: horizontal ? errorY : errorX,