ElasticReceiptTokenBase_v1.increaseAllowance lacks of validRecipient modifier

[hats-bug-reporter]

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Submission hash (on-chain): 0xdfafe3bb77118d9c96ff1b19049bed1aafc6c4b1c63c2e825604c7c73860a909
Severity: low

Description:
Description
ElasticReceiptTokenBase_v1.increaseAllowance and ElasticReceiptTokenBase_v1.approve have sililar function that add/set _tokenAllowances.
For ElasticReceiptTokenBase_v1.approve, the function uses validRecipient, but increaseAllowancedoesn't use validRecipient.

Attack Scenario
Without the validRecipient, ElasticReceiptTokenBase_v1.increaseAllowance can be used to set _tokenAllowances to address(0) or address(this)

Attachments

1. Proof of Concept (PoC) File

2. Revised Code File (Optional)

[PlamenTSV]

Informational, no value loss.