[minor] reload auto email report doctype before settings format to xlsx

[mbauskar]

Traceback (most recent call last):
  File "/usr/local/Cellar/python/2.7.13/Frameworks/Python.framework/Versions/2.7/lib/python2.7/runpy.py", line 174, in _run_module_as_main
    "__main__", fname, loader, pkg_name)
  File "/usr/local/Cellar/python/2.7.13/Frameworks/Python.framework/Versions/2.7/lib/python2.7/runpy.py", line 72, in _run_code
    exec code in run_globals
  File "/Users/makarandbauskar/workspace/frappe/dev-frappe-bench/apps/frappe/frappe/utils/bench_helper.py", line 91, in <module>
    main()
  File "/Users/makarandbauskar/workspace/frappe/dev-frappe-bench/apps/frappe/frappe/utils/bench_helper.py", line 17, in main
    click.Group(commands=commands)(prog_name='bench')
  File "/Users/makarandbauskar/workspace/frappe/dev-frappe-bench/env/lib/python2.7/site-packages/click/core.py", line 722, in __call__
    return self.main(*args, **kwargs)
  File "/Users/makarandbauskar/workspace/frappe/dev-frappe-bench/env/lib/python2.7/site-packages/click/core.py", line 697, in main
    rv = self.invoke(ctx)
  File "/Users/makarandbauskar/workspace/frappe/dev-frappe-bench/env/lib/python2.7/site-packages/click/core.py", line 1066, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "/Users/makarandbauskar/workspace/frappe/dev-frappe-bench/env/lib/python2.7/site-packages/click/core.py", line 1066, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "/Users/makarandbauskar/workspace/frappe/dev-frappe-bench/env/lib/python2.7/site-packages/click/core.py", line 895, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "/Users/makarandbauskar/workspace/frappe/dev-frappe-bench/env/lib/python2.7/site-packages/click/core.py", line 535, in invoke
    return callback(*args, **kwargs)
  File "/Users/makarandbauskar/workspace/frappe/dev-frappe-bench/env/lib/python2.7/site-packages/click/decorators.py", line 17, in new_func
    return f(get_current_context(), *args, **kwargs)
  File "/Users/makarandbauskar/workspace/frappe/dev-frappe-bench/apps/frappe/frappe/commands/__init__.py", line 24, in _func
    ret = f(frappe._dict(ctx.obj), *args, **kwargs)
  File "/Users/makarandbauskar/workspace/frappe/dev-frappe-bench/apps/frappe/frappe/commands/site.py", line 216, in migrate
    migrate(context.verbose, rebuild_website=rebuild_website)
  File "/Users/makarandbauskar/workspace/frappe/dev-frappe-bench/apps/frappe/frappe/migrate.py", line 31, in migrate
    frappe.modules.patch_handler.run_all()
  File "/Users/makarandbauskar/workspace/frappe/dev-frappe-bench/apps/frappe/frappe/modules/patch_handler.py", line 29, in run_all
    if not run_single(patchmodule = patch):
  File "/Users/makarandbauskar/workspace/frappe/dev-frappe-bench/apps/frappe/frappe/modules/patch_handler.py", line 63, in run_single
    return execute_patch(patchmodule, method, methodargs)
  File "/Users/makarandbauskar/workspace/frappe/dev-frappe-bench/apps/frappe/frappe/modules/patch_handler.py", line 83, in execute_patch
    frappe.get_attr(patchmodule.split()[0] + ".execute")()
  File "/Users/makarandbauskar/workspace/frappe/dev-frappe-bench/apps/frappe/frappe/patches/v8_1/update_format_options_in_auto_email_report.py", line 14, in execute
    doc.save()
  File "/Users/makarandbauskar/workspace/frappe/dev-frappe-bench/apps/frappe/frappe/model/document.py", line 230, in save
    return self._save(*args, **kwargs)
  File "/Users/makarandbauskar/workspace/frappe/dev-frappe-bench/apps/frappe/frappe/model/document.py", line 266, in _save
    self._validate()
  File "/Users/makarandbauskar/workspace/frappe/dev-frappe-bench/apps/frappe/frappe/model/document.py", line 401, in _validate
    self._validate_selects()
  File "/Users/makarandbauskar/workspace/frappe/dev-frappe-bench/apps/frappe/frappe/model/base_document.py", line 540, in _validate_selects
    value, comma_options))
  File "/Users/makarandbauskar/workspace/frappe/dev-frappe-bench/apps/frappe/frappe/__init__.py", line 320, in throw
    msgprint(msg, raise_exception=exc, title=title, indicator='red')
  File "/Users/makarandbauskar/workspace/frappe/dev-frappe-bench/apps/frappe/frappe/__init__.py", line 310, in msgprint
    _raise_exception()
  File "/Users/makarandbauskar/workspace/frappe/dev-frappe-bench/apps/frappe/frappe/__init__.py", line 283, in _raise_exception
    raise raise_exception(encode(msg))
frappe.exceptions.ValidationError:  Format cannot be "XLSX". It should be one of "HTML", "XLS", "CSV"