Improve Oracle error handling

[oleksandrSydorenkoJ]

Preconditions:
Active schain medium type
All nodes active and run
Installed oracle-demo

Version:
skalenetwork/schain:3.16.1-beta.2

Steps to reproduce:

1. Run examples.py in Oracle-demo repo
2. check response on eth_blockNumber, eth_gasPrice, eth_getBlockByNumber, eth_getBlockByHash and other eth_methods

Expected state:
In Actual release for Oracle all eth_methods except eth_call are not allowed, Skaled should return readable log output if method valid but not supported

Actual state:
Skaled returns an uninformative error to all eth methods except eth_call

Logs:

Request >>>  {'id': 83, 'jsonrpc': '2.0', 'method': 'oracle_submitRequest', 'params': ['{"cid":123123,"uri":"eth://","jsps":["/result"],""encoding":"json","ethApi":"eth_gasPrice","params":[],"time":1681822602000,"pow":1337}']}
Response <<<  {'error': {'code': 24, 'data': None, 'message': 'Invalid oracle spec in submitOracleRequest Oracle check failed: Unparsable Oracle spec:{"cid":123123,"uri":"eth://","jsps":["/result"],""encoding":"json","ethApi":"eth_gasPrice","params":[],"time":1681822602000,"pow":1337}'}, 'id': 83, 'jsonrpc': '2.0'}

Note:
The same topic - the Unparsable Oracle spec error output if skaled couldn't return the result

1. Send oracle request to web2 with bad latency
   logs from skaled:

[2023-04-18 12:36:03.581] [46:main] [error] 131990:Curl easy perform failed for url: http://httpbin.org/anything with error code:28

logs from Oracle:

Response <<<  {'error': {'code': 24, 'data': None, 'message': 'Invalid oracle spec in submitOracleRequest Oracle check failed: Unparsable Oracle spec:{"cid":123123,"uri":"http://httpbin.org/anything","jsps":["/url","/headers/Content-Length"],"post":"string=string_value","encoding":"json,"time":1681821585000,"pow":2348}'}, 'id': 83, 'jsonrpc': '2.0'}

2. Valid but unsupported methods:
   Logs from skaled

2023-04-18 12:44:22.921177   http://1.1.1.1:31223 >>> {"id":83,"jsonrpc":"2.0","method":"oracle_submitRequest","params":["{\"cid\":1,\"uri\":\"eth://\",\"jsps\":[\"/result\"],\"\"encoding\":\"json\",\"ethApi\":\"eth_gasPrice\",\"params\":[],\"time\":1681821862000,\"pow\":1900}"]}
2023-04-18 12:44:22.921260   {"cid":1,"uri":"eth://","jsps":["/result"],""encoding":"json","ethApi":"eth_gasPrice","params":[],"time":1681821862000,"pow":1900}
[2023-04-18 12:44:22.921] [config] [error] Invalid oracle spec in submitOracleRequest Oracle check failed: Unparsable Oracle spec:{"cid":1,"uri":"eth://","jsps":["/result"],""encoding":"json","ethApi":"eth_gasPrice","params":[],"time":1681821862000,"pow":1900}
2023-04-18 12:44:22.921425   http://1.1.1.1:31223 <<< {"error":{"code":24,"data":null,"message":"Invalid oracle spec in submitOracleRequest Oracle check failed: Unparsable Oracle spec:{\"cid\":1,\"uri\":\"eth://\",\"jsps\":[\"/result\"],\"\"encoding\":\"json\",\"ethApi\":\"eth_gasPrice\",\"params\":[],\"time\":1681821862000,\"pow\":1900}"},"id":83,"jsonrpc":"2.0"}

logs from Oracle:

Request >>>  {'id': 83, 'jsonrpc': '2.0', 'method': 'oracle_submitRequest', 'params': ['{"cid":1,"uri":"eth://","jsps":["/result"],""encoding":"json","ethApi":"eth_gasPrice","params":[],"time":1681821862000,"pow":1900}']}
Response <<<  {'error': {'code': 24, 'data': None, 'message': 'Invalid oracle spec in submitOracleRequest Oracle check failed: Unparsable Oracle spec:{"cid":1,"uri":"eth://","jsps":["/result"],""encoding":"json","ethApi":"eth_gasPrice","params":[],"time":1681821862000,"pow":1900}'}, 'id': 83, 'jsonrpc': '2.0'}

3. No space after error message: not allowed in Oracle urishttp

Response <<<  {'error': {'code': 23, 'data': None, 'message': 'Invalid oracle spec in submitOracleRequest Oracle check failed: IP addresses not allowed in Oracle urishttp://146.59.55.165:3009/status/schains'}, 'id': 83, 'jsonrpc': '2.0'}

[oleksandrSydorenkoJ]

related to #754