Fix the fetching of fundamentals

[PaulRenvoise]

As of now, the fetching of fundamentals is broken for some (all?) tickers (e.g. BIM.PA, AF.PA, IBM, etc.).

The reason for that is located in the _get_fundamentals method implemented in base.py, between the lines 280 and 285: the url var (containing the base_url and the ticker) has "/holders" appended, and when fetching the fundamentals, only "/financials" is appended again, instead of replacing "/holders".

This PR fixes the issue.

Before:

import yfinance as yf

yf.Ticker('BIM.PA').earnings
#=> Empty DataFrame
#=> Columns: [Open, High, Low, Close, Adj Close, Volume]
#=> Index: []

After:

import yfinance as yf

yf.Ticker('BIM.PA').financials
#=>          Revenue   Earnings
#=> Year
#=> 2016  2103200000  179100000
#=> 2017  2288200000  238100000
#=> 2018  2421300000  256500000
#=> 2019  2674800000  272800000

[PaulRenvoise]

Closes #191, #465, #474, #475, #423, #419

[muran123]

Thank you. Your fix solved the isuee. Would be great to have it in the next release.

[sedziwoj]

So when is next release, because I change it by hand, and this bug blocking useful informations.

[mvanaltvorst]

This PR works great, I am not sure why it isn't merged yet.

[ravidparikh92]

I am still facing this issue. When will it be fixed in the next release. Thank you.

[jiayanguo]

Ya, I am facing the same issue.

[Charmik]

can you merge this MR? it's commited in October

[jeremyleonardo]

fixed the problem for me