Fixed rate exchange tests (#513)

* Creating an inital Fixed rate exchange test

* Testing additional fields

* Testing all fields on fixed rate exchange

* Splitting up tests

* Splitting up fixed rate exachange tests

* Creating test for fixed rate price updates

* Adding test for updating allowed swapper

* Fixing templateId test

* Testing fixed rate excahnge updates

* Testing deactivate exchange

* Testing activate and deactive exchange

* Updating activate and deactivate minting

* Testing all fields of swaps after buying a DT

* Creating testing for selling a fixed rate DT

* Creating a constant for sleep ms

Author: jamiehewitt15

package.json

@@ -24,6 +24,7 @@
     "deploy:local-barge": "graph deploy oceanprotocol/ocean-subgraph subgraph.yaml -l $npm_package_version --debug --ipfs http://172.15.0.16:5001 --node http://172.15.0.15:8020",
     "test": "npm run codegen && npm run lint && npm run type-check",
     "test-integration": "TS_NODE_PROJECT='test/integration/tsconfig.json' mocha --config=test/integration/.mocharc.json --node-env=test --exit 'test/integration/**/*.test.ts'",
+    "test-fixed": "TS_NODE_PROJECT='test/integration/tsconfig.json' mocha --config=test/integration/.mocharc.json --node-env=test --exit 'test/integration/FixedRateExchange.test.ts'",
     "lint": "eslint --ignore-path .gitignore --ext .js --ext .ts --ext .tsx .",
     "lint:fix": "eslint --ignore-path .gitignore --ext .js,.ts,.tsx . --fix",
     "format": "prettier --ignore-path .gitignore './**/*.{css,yml,js,ts,tsx,json,yaml}' --write",