Fix invalid value for weights_summary

[rohitgr7]

What does this PR do?

The main fix here is if you do model.summarize(None) it still prints the total params, trainable params, ... and if you do model.summarize('invalid_string or value') it won't raise an error and will act like None.

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[codecov]

Codecov Report

Merging #5296 (03f8684) into master (15a400b) will increase coverage by 0%.
The diff coverage is 100%.

@@          Coverage Diff           @@
##           master   #5296   +/-   ##
======================================
  Coverage      93%     93%           
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  Files         134     134           
  Lines        9950    9954    +4     
======================================
+ Hits         9261    9266    +5     
+ Misses        689     688    -1     

[Borda]

@rohitgr7 as you are changing API we need to move it to 1.2
mind rebase on feature 1.2 🐰

[rohitgr7]

I thought I created this branch on top of release branch only. Will update it.

[carmocca]

LGTM. One thing:

Why not keep mode to avoid the API change?

[awaelchli]

+1 for keeping mode please :)

[rohitgr7]

I did that to have the exception at one place for both the cases.

trainer = Trainer(weights_summary='sdf')
model.summarize(weights_summary='sdf')

Will update this then.

[Borda]

@rohitgr7 is it as a bugfix for master or a feature for 1.2? there is some confusion as it is a 1.2 milestone but the target is master

[rohitgr7]

bugfix now. forgot to update the milestone. Updated!

[carmocca]

I did that to have the exception at one place for both the cases.

Didn't realize the API was inconsistent. I like what you propose. We can do it in another PR