Implementing the user-story for sign request expiry and add qml tests
+ other minor fixes
## Acceptance Criteria
```
//Always show the expiration
Given the sign/transaction request dialog is shown
When request has an expiration date
Then the user sees a 1 minute countdown in the dialog
```
```
// Show 1 minute timer
Given the sign/transaction request dialog is shown
When the request has 1 minute or less before expiring
Then the user sees a 1 second countdown in the dialog
```
```
Given the sign/transaction dialog is open
When the request expires
Then the Accept button is removed
And the only option for the user is to close the dialog
```
```
Given the sign/transaction request dialog is open
When the request expired
Then the `Sign` and `Reject` buttons are removed
And the `Close` button is visible
```
```
Given the sign/transaction request expired
Then a toast message is showing
And it contains the "<dapp domain> sign request timed out" message
```
```
Given the sign/transaction request dialog is open
When the request expired
Then the sign/transaction request dialog is still visible
```
```
Given the sign/transaction request expires
Then a console message is shown
And it contains 'WC WalletConnectSDK.onSessionRequestExpire; id: ${id}`'
```
Implement the initial Pairing user workflow and disconnect option for
the first session.
Also
- rename pairing modal accordingly (`PairWCModal.qml`) to make room for the proper
`ConnectDAppModal.qml`
- basic tests for service helpers
- update storybook to reflect the new user workflows
Closes#14607
Alex Jbanca
Stefan