fontforge update for python

I found that configure didn't find the python.pc files using pkg-config without explicitly updating the PKG_CONFIG_PATH from the brew file. Sorry if this the incorrect way of going about this, no amount of adding depends_on 'python' was letting brew include python into the PKG_CONFIG_PATH.
I checked and got this:

```
==> ./configure --prefix=/usr/local/Cellar/fontforge/HEAD --enable-double --with
checking for update-mime-database... :
checking for update-desktop-database... :
checking for plutil... /usr/bin/plutil
checking whether /usr/local/bin/python version is >= 2.7... no
configure: error: Python interpreter is too old

READ THIS: https://github.com/Homebrew/homebrew/wiki/troubleshooting

These open issues may also help:
fontforge update for python (https://github.com/Homebrew/homebrew/pull/31226)
fontforge: Update formula for 2.0 (https://github.com/Homebrew/homebrew/pull/27221)
```