[FEATURE REQ] please make it easier to instantiate objects

**Is your feature request related to a problem? Please describe.**

I writing unit tests for some code which uses the `SecretClient`.

Imagine something like:
```java
SecretClient client = mock(SecretClient.class);
when(client.getSecret("foo")).thenReturn(new KeyVaultSecret("foo", "secret"));
```

But the `KeyVaultSecret` has many properties my application uses, which I need to set, but there are no setters!

I have had to scrap together all sorts of workaround to get to this — here's how it looks:

```java
// 1. create a bundle, some properties have no setter, so you need to serialize from JSON
SecretBundle bundle = SecretBundle.fromJson(createReader(
"""
{
"attributes": {
"created": %d,
"recoveryLevel": "%s",
"enabled": true
}
}
""".formatted(
Instant.now().getLong(MILLI_OF_SECOND),
RECOVERABLE
)));

// 2. set the ID this way also sets the vault, name, and version
bundle.setId("%s/secrets/%s/%s".formatted(vault.replaceAll("/$",""), name, version));
bundle.setValue(new String(Hex.encodeHex(value)));

// 3. use this helper to make the secret from the bundle
KeyVaultSecret secret = createKeyVaultSecret(bundle);

// 4. finally, set some other stuff which are required
secret.getProperties().setExpiresOn(Instant.now().plusSeconds(600).atOffset(ZoneOffset.UTC));
return secret;
```

This is just one example, even harder is generic iterator classes like `PagedIterable` 🥵

**Describe the solution you'd like**

Builder patter would be ideal — eg:
```java
KeyVaultSecret secret = new KeyVaultSecret.Builder()
.vault("https://example.vault.azure.net/")
.name("example")
.version("aaaaa")
.value(v)
.build()
```

Additionally, maybe default `createdOn`, enabled, etc

**Describe alternatives you've considered**

more setters?

**Additional context**

NA

**Information Checklist**
Kindly make sure that you have added all the following information above and checkoff the required fields otherwise we will treat the issuer as an incomplete report
- [x] Description Added
- [x] Expected solution specified