Fixed error on attempting to revert() on store with summary records

[jskupsik]

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[jskupsik]

Fixed the following silent console error:

It occurred when users would cancel editing on a grid with a summary row via the store.revert() method.

Fixed to follow the documentation on StoreRecordConfig, as we were trying to "re-enhance" an already-frozen data object:

    /**
     * Data for this StoreRecord, pre-processed if applicable by `Store.processRawData()` and
     * `Field.parseVal()`. Note this must be a new object dedicated to this StoreRecord.
     * This object will be enhanced with an id and frozen.
     */
    data: PlainObject;

[amcclain]

Thanks for the fix!