Minor typo fixes for Instana propagator (#376)

* Minor typo fixes for Instana propagator

* Reverted composer.json change

* Update src/Propagation/Instana/README.md

---------

Co-authored-by: Brett McBride <[email protected]>

Author: HeenaBansal20

src/Propagation/Instana/.phan/config.php

@@ -42,7 +42,7 @@
     //
     // Note that the **only** effect of choosing `'5.6'` is to infer that functions removed in php 7.0 exist.
     // (See `backward_compatibility_checks` for additional options)
-    'target_php_version' => '8.0',
+    'target_php_version' => '8.1',
 
     // If enabled, missing properties will be created when
     // they are first seen. If false, we'll report an

src/Propagation/Instana/README.md

@@ -31,7 +31,7 @@ Both of the above have extract and inject methods available to extract and injec
 For Baggage propagation, use opentelemetry's MultiTextMapPropagator, and pass the array list of propagators i.e Instana and Baggage propagator as below.
 
 ```
-$propagator = new MultiTextMapPropagator(InstantPropagator::getInstance(), BaggagePropagator::getInstance());
+$propagator = new MultiTextMapPropagator([InstanaPropagator::getInstance(), BaggagePropagator::getInstance()]);
 ```
 
 ## Propagator Details