update open api specs for string search

docs/openapi.yaml

@@ -297,7 +297,7 @@ paths:
 
         - name: q
           in: query
-          description: 'The attribute query is used for querying <b> allowed quantitative</b> properties. <br/> Used to query on a value of a resource attribute using `<`,`>`,`<=`,`>=`,`!=`, `==` operators. <br/> For e.g, attribute > value, attribute < value, attribute >= value, attribute <= value, attribute != value and attribute == value. <br/> Allowed values for all operators is double. <br/> For the operator `==` if the query is on `id` then the only value allowed is an `data exchange ID` of a resource.'
+          description: 'The attribute query is used for querying <b> allowed quantitative</b> properties. <br/> Used to query on a value of a resource attribute using `<`,`>`,`<=`,`>=`,`!=`, `==` operators. <br/> Additionally, a user can search a resource attribute with a alpha-numeric value using `==` operator. For e.g, attribute > value, attribute < value, attribute >= value, attribute <= value, attribute != value and attribute == value. <br/> Allowed values for all operators is double, and as a special case alpha-nmeric values are allowed for `==`. <br/> For the operator `==` if the query is on `id` then the only value allowed is an `data exchange ID` of a resource.'
           schema:
             type: string
             maxLength: 512
@@ -402,6 +402,12 @@ paths:
             curl --location -g --request GET 'https://example.com/ngsi-ld/v1/entities?id=UUID&geoproperty=location&georel=near;maxDistance=10&geometry=Point&coordinates=[21.178,72.834]&options=count' \
             --header 'token: <tokenValue>'
 
+        - lang: 'cURL'
+          label: 'search by string attribute'
+          source: |
+            curl --location --request GET 'https://example.com/ngsi-ld/v1/entities?id=UUID&offset=0&limit=10&q=license_plate==GJ05BU3663' \
+            --header 'token: <tokenValue>'
+
 
       deprecated: false
       description: |
@@ -449,7 +455,7 @@ paths:
         The attribute query is used for querying <b> allowed quantitative</b> properties. 
           - Used to query on a value of a resource attribute using `<`,`>`,`<=`,`>=`,`!=`,`==` operators. 
           - For e.g, attribute > value, attribute < value, attribute >= value, attribute <= value and attribute == value. 
-          - Allowed values for all operators is double. 
+          - Allowed values for all operators is double and alphanumeric for `==` operator. 
           - For the operator `==` if the query is on `id` then the only value allowed is an `data exchange ID` of a resource. 
           - e.g, `q=attribute-name>attribute-value`