Replace Loader by component from SRC

[alongoni]

Closes #2100 and #2140
Now we use the Loader component from SRC
https://components.gnosis-safe.io/?path=/docs/feedback-loader--loader

[github-actions]

CLA Assistant Lite All Contributors have signed the CLA.

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Type	Occurrences	Fixable
Errors	0	0
Warnings	0	0
Ignored	0	N/A

• Result: ✅ success
• Annotations: 0 total

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[github-actions]

• Safe Multisig app rinkeby

[github-actions]

• Safe Multisig app mainnet

[francovenica]

I think this icon is black instead of green, is too fast for me to confirm if it is the same component with different color or a different component all together. This icon shows up when you open "New transaction" and then pick one of the 3 options. (is the loading of the form)

Edit:
It seems to be the correct component, but is black instead of green for some reason

[francovenica]

The rest of the loaders looks fine.

[francovenica]

Safe and env:
https://pr2119--safereact.review.gnosisdev.com/rinkeby/app/#/safes/0x9913B9180C20C6b0F21B6480c84422F6ebc4B808/transactions

The loaders reported were fixed. They are shown in green just fine

I don't have the issue of the scroll bar wiggling anymore (ticket #2140). I recreated the same scenario where I reported the issue and it doesn't happen anymore.

[github-actions]

ESLint Summary View Full Report

Annotations are provided inline on the Files Changed tab. You can also see all annotations that were generated on the annotations page.

Type	Occurrences	Fixable
Errors	0	0
Warnings	0	0
Ignored	0	N/A

• Result: ✅ success
• Annotations: 0 total

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^{Report generated by eslint-plus-action}

[katspaugh]

Awesome! 👏