Check Fetch InstrumentationScope from ReadableSpan for PHP (#2622)

OTEL-PHP at some point switched to using InstrumentationScope instead of InstrumentationLibrary everywhere, which incidentally satisfied the ["Fetch InstrumentationScope from ReadableSpan"](https://github.com/open-telemetry/opentelemetry-specification/blob/65624332cadac9990923f442e96a424c308e502c/specification/common/mapping-to-non-otlp.md#instrumentationscope) part of the spec (otel-php is still alpha so it seemed ok to not deprecate the instrumentation library and just remove it's use entirely)

Related issues #
open-telemetry/opentelemetry-php#705

Related [OTEP(s)](https://github.com/open-telemetry/oteps) #
Don't think it was an OTEP but open-telemetry/opentelemetry-specification#2276 is where the push for the change originally came from I believe

spec-compliance-matrix.md

@@ -83,7 +83,7 @@ formats is required. Implementing more than one format is optional.
 | [SpanLimits](specification/trace/sdk.md#span-limits)                                             | X        | +   | +    |     | +      | +    | +      | +   |      | -   |      | +     |
 | [Built-in `SpanProcessor`s implement `ForceFlush` spec](specification/trace/sdk.md#forceflush-1) |          |     | +    |     | +      | +    | +      | +   | +    | +   | +    |       |
 | [Attribute Limits](specification/common/README.md#attribute-limits)                              | X        |     | +    |     |        |      | +      | +   |      |     |      |       |
-| Fetch InstrumentationScope from ReadableSpan                                                     |          |     | +    |     |        |      |        |     |      |     |      |       |
+| Fetch InstrumentationScope from ReadableSpan                                                     |          |     | +    |     |        |      |        | +   |      |     |      |       |
 
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