Feat/display address external link

[heronlancellot]

Closes #213

• created new component BlockExplorerExternalLinkButton.tsx
• fix word correction in search-bar
• adjust the ApproveTokenCard to fill the address + external link
• moved setTokenApprovalStatus(TokenApprovalStatus.APPROVE_IN_YOUR_WALLET) to else condition in ApproveTokenCard
• add getTokenContract() to get the contractAddress

[vercel]

@heronlancellot is attempting to deploy a commit to the Shared Blockful's projects Team on Vercel.

A member of the Team first needs to authorize it.

[FrancoAguzzi]

Suggested change

	if (!token.contract) {
	address = (token as ERC721).contractMetadata?.address;
	} else {
	address = new EthereumAddress(token.contract as string);
	}
	if (!token.contract) {
	address = (token as ERC721).contractMetadata?.address;
	} else if (typeof token.contract === "string") {
	address = new EthereumAddress(token.contract);
	}
	if (!address) throw new Error(`Token contract address not defined for ${getTokenName(token)}`)

[0xneves]

Address is not yet defined so the proposal will not work, I changed in a way to accept undefined as well but throwing for it. Also changed the conditionals into a double ternary