Load secure values from multiple credential entries on Windows

[t1m0thyj]

On Windows the maximum credential length is 2560 bytes. If the JSON object in Zowe/secure_config_props exceeds this length, Zowe CLI works around the limitation by splitting the credential string across multiple entries. The final one is terminated by a NUL byte (\0). For example:
Zowe/secure_config_props-1

{"C:/Users/User/.zowe/zowe.con

Zowe/secure_config_props-2

fig.json":{...}}␀

[zFernand0]

Documentation:

• Look for CredentialBlobSize in https://learn.microsoft.com/en-us/windows/win32/api/wincred/ns-wincred-credentiala

Node.js SDK implementation:
https://github.com/zowe/imperative/blob/9269753532a0201284aa07417a9d2be9e1598ded/packages/security/src/DefaultCredentialManager.ts#L293-L310