fix: share_transfer display wrong currency symbo

In multi-companies setting, on amount and rate field of  Share Transfer
doctype are displaying wrong currency symbol, when create a
Share Transfer of others company that has different currency than
the main company. This due to the lack of `options` on those fields.

To fix this, add `options` to `amount` and `rate` fields.
diff --git a/erpnext/accounts/doctype/share_transfer/share_transfer.json b/erpnext/accounts/doctype/share_transfer/share_transfer.json
index 59a3053..51f2ac1 100644
--- a/erpnext/accounts/doctype/share_transfer/share_transfer.json
+++ b/erpnext/accounts/doctype/share_transfer/share_transfer.json
@@ -124,6 +124,7 @@
    "fieldname": "rate",
    "fieldtype": "Currency",
    "label": "Rate",
+   "options": "Company:company:default_currency",
    "reqd": 1
   },
   {
@@ -147,6 +148,7 @@
    "fieldname": "amount",
    "fieldtype": "Currency",
    "label": "Amount",
+   "options": "Company:company:default_currency",
    "read_only": 1
   },
   {