Add OtlpAwsLogExporter and OtlpAwsSpanExporter

[liustve]

Background:
#358
The above PR got rid of OtlpAwsSpanExporter and OtlpAwsLogExporter as to use the default upstream exporters as that was a cleaner approach.

However, we need the OtlpAwsSpanExporter and OtlpAwsLogExporter classes to support later requirements for Gen AI as we need to override the export method.

Description of changes:
This PR reintroduces the OtlpAwsSpanExporter and OtlpAwsLogExporter classes to support later requirements for Gen AI as we need to override the export method.

This change does not introduce anything new and the Sigv4 span + logs exporter still work as intended:

Logs:

{
    "resource": {
        "attributes": {
            "aws.local.service": "test",
            "service.name": "test",
            "cloud.region": "us-west-2",
            "host.type": "c5.4xlarge",
            "cloud.availability_zone": "us-west-2c",
            "telemetry.sdk.name": "opentelemetry",
            "telemetry.sdk.language": "python",
            "cloud.provider": "aws",
            "cloud.account.id": "571600841604",
            "telemetry.sdk.version": "1.27.0",
            "host.name": "ip-172-31-7-29.us-west-2.compute.internal",
            "cloud.platform": "aws_ec2",
            "host.id": "i-0b04d6affbae7d629",
            "telemetry.auto.version": "0.9.0.dev0-aws"
        }
    },
    "scope": {
        "name": "opentelemetry.sdk._logs._internal"
    },
    "timeUnixNano": 1747074906326769664,
    "observedTimeUnixNano": 1747074906326822815,
    "severityNumber": 9,
    "severityText": "INFO",
    "body": "127.0.0.1 - - [12/May/2025 18:35:06] \"GET /server_request HTTP/1.1\" 200 -",
    "attributes": {
        "code.filepath": "/home/ec2-user/.local/lib/python3.9/site-packages/werkzeug/_internal.py",
        "otelTraceSampled": false,
        "code.function": "_log",
        "code.lineno": 97,
        "otelTraceID": "0",
        "otelSpanID": "0",
        "otelServiceName": "test"
    },
    "traceId": "",
    "spanId": ""
}

Spans:

{
    "resource": {
        "attributes": {
            "aws.local.service": "test",
            "service.name": "test",
            "cloud.region": "us-west-2",
            "host.type": "c5.4xlarge",
            "cloud.availability_zone": "us-west-2c",
            "telemetry.sdk.name": "opentelemetry",
            "telemetry.sdk.language": "python",
            "cloud.provider": "aws",
            "cloud.account.id": "571600841604",
            "telemetry.sdk.version": "1.27.0",
            "host.name": "ip-172-31-7-29.us-west-2.compute.internal",
            "cloud.platform": "aws_ec2",
            "host.id": "i-0b04d6affbae7d629",
            "telemetry.auto.version": "0.9.0.dev0-aws"
        }
    },
    "scope": {
        "name": "opentelemetry.instrumentation.flask",
        "version": "0.48b0"
    },
    "traceId": "68223f2d375733237e24512171012437",
    "spanId": "34dd5a89d7a21fdf",
    "flags": 256,
    "name": "GET /",
    "kind": "SERVER",
    "startTimeUnixNano": 1747074861988123056,
    "endTimeUnixNano": 1747074861988911516,
    "durationNano": 788460,
    "attributes": {
        "net.host.name": "localhost:8082",
        "aws.local.service": "test",
        "net.peer.port": 57356,
        "telemetry.extended": "true",
        "http.target": "/",
        "http.flavor": "1.1",
        "net.peer.ip": "127.0.0.1",
        "http.host": "localhost:8082",
        "aws.local.environment": "ec2:default",
        "http.status_code": 404,
        "aws.local.operation": "GET /",
        "aws.span.kind": "LOCAL_ROOT",
        "http.server_name": "127.0.0.1",
        "http.user_agent": "curl/8.5.0",
        "net.host.port": 8082,
        "PlatformType": "AWS::EC2",
        "http.method": "GET",
        "http.response.status_code": 404,
        "http.scheme": "http"
    },
    "status": {
        "code": "UNSET"
    }
}

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