Fix datetime tick storage

[softlion]

What kind of change does this PR introduce? (Bug fix, feature, docs update, ...)

Fix bug where datetime is stored as local and restored as UTC forgetting the offset.

What is the current behavior? (You can also link to an open issue here)

stores 12:00 UTC+1
restores 12.00 UTC+0

What is the new behavior (if this is a feature change)?

stores 12:00 UTC+1
restores 11.00 UTC+0

Does this PR introduce a breaking change?

No

Please check if the PR fulfills these requirements

• The commit follows our guidelines: https://github.com/Akavache/Akavache/blob/master/CONTRIBUTING.md
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

Other information:

[softlion]

My pr introduced a bug showing an infinite loop of calls exhausting the stack:
edit: it's not my pr, it's your code lol :)
edit2: it's not my pr, it's not your code. It's when an existingContractResolver is non null and derives from DefaultContractResolver. Then it loops ...

Newtonsoft_Json_Utilities_ThreadSafeStore_2_TKey_REF_TValue_REF_Get_TKey_REF + 29119496 (ThreadSafeStore.cs:64)
Newtonsoft_Json_Serialization_DefaultContractResolver_ResolveContract_System_Type + 29123632 (DefaultContractResolver.cs:198)
Akavache_JsonDateTimeContractResolver_CreateContract_System_Type + 38540100 (/D:\a\1\s\src\Akavache.Core\JsonDateTimeContractResolver.cs:23)
System_Collections_Concurrent_ConcurrentDictionary_2_TKey_REF_TValue_REF_GetOrAdd_TKey_REF_System_Func_2_TKey_REF_TValue_REF + 180
Newtonsoft_Json_Utilities_ThreadSafeStore_2_TKey_REF_TValue_REF_Get_TKey_REF + 29119496 (ThreadSafeStore.cs:64)
Newtonsoft_Json_Serialization_DefaultContractResolver_ResolveContract_System_Type + 29123632 (DefaultContractResolver.cs:198)
Akavache_JsonDateTimeContractResolver_CreateContract_System_Type + 38540100 (/D:\a\1\s\src\Akavache.Core\JsonDateTimeContractResolver.cs:23)
System_Collections_Concurrent_ConcurrentDictionary_2_TKey_REF_TValue_REF_GetOrAdd_TKey_REF_System_Func_2_TKey_REF_TValue_REF + 180
Newtonsoft_Json_Utilities_ThreadSafeStore_2_TKey_REF_TValue_REF_Get_TKey_REF + 29119496 (ThreadSafeStore.cs:64)
Newtonsoft_Json_Serialization_DefaultContractResolver_ResolveContract_System_Type + 29123632 (DefaultContractResolver.cs:198)
Akavache_JsonDateTimeContractResolver_CreateContract_System_Type + 38540100 (/D:\a\1\s\src\Akavache.Core\JsonDateTimeContractResolver.cs:23)
System_Collections_Concurrent_ConcurrentDictionary_2_TKey_REF_TValue_REF_GetOrAdd_TKey_REF_System_Func_2_TKey_REF_TValue_REF + 180
Newtonsoft_Json_Utilities_ThreadSafeStore_2_TKey_REF_TValue_REF_Get_TKey_REF + 29119496 (ThreadSafeStore.cs:64)
Newtonsoft_Json_Serialization_DefaultContractResolver_ResolveContract_System_Type + 29123632 (DefaultContractResolver.cs:198)
Akavache_JsonDateTimeContractResolver_CreateContract_System_Type + 38540100 (/D:\a\1\s\src\Akavache.Core\JsonDateTimeContractResolver.cs:23)
System_Collections_Concurrent_ConcurrentDictionary_2_TKey_REF_TValue_REF_GetOrAdd_TKey_REF_System_Func_2_TKey_REF_TValue_REF + 180
Newtonsoft_Json_Utilities_ThreadSafeStore_2_TKey_REF_TValue_REF_Get_TKey_REF + 29119496 (ThreadSafeStore.cs:64)```

[glennawatson]

Lets take this one to an issue.