Remove width attr from BackgroundImage filter element

[seanforyou23]

This PR removes the width attribute for the filter element in BackgroundImage. Looks like it could also be set to the default value of 120%, but omitting it also seems to work so taking that route. Should help clear console errors when using this component.

What: Closes #3250

[patternfly-build]

PF3 preview: https://patternfly-react-pr-3758-pf3.surge.sh
PF4 preview: https://patternfly-react-pr-3758.surge.sh
A11y report: https://patternfly-react-pr-3758-coverage.surge.sh

[codecov-io]

Codecov Report

Merging #3758 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #3758   +/-   ##
=======================================
  Coverage   70.96%   70.96%           
=======================================
  Files         785      785           
  Lines       10632    10632           
  Branches     2313     2313           
=======================================
  Hits         7545     7545           
  Misses       2656     2656           
  Partials      431      431

Flag	Coverage Δ
#misc	95.45% <ø> (ø)	⬆️
#patternfly3	85.89% <ø> (ø)	⬆️
#patternfly4	59.94% <ø> (ø)	⬆️

Impacted Files	Coverage Δ
...src/components/BackgroundImage/BackgroundImage.tsx	100% <ø> (ø)	⬆️

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[dlabrecq]

LGTM

[redallen]

I tried to remove this attribute a few months ago. I settled for setting it to "" instead of "0" because of a Firefox bug I think? (see #2693) However, this PR appears to work in Firefox.

If @mcoker approves, this is good by me and we should change the HTML in Core too.

[mcoker]

LGTM! This was originally implemented due to an issue in Chrome - patternfly/patternfly#607

But I tested in chrome, safari, and firefox, and looks fine!