updated rxjs to 6+

[orthodoc]

For ionic 4 projects that use rxjs 6

[coveralls]

Pull Request Test Coverage Report for Build 131

• 20 of 32 (62.5%) changed or added relevant lines in 7 files are covered.
• 1 unchanged line in 1 file lost coverage.
• Overall coverage decreased (-0.01%) to 77.139%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/native/network.ts	1	3	33.33%
src/native/nfc.ts	1	11	9.09%

Files with Coverage Reduction	New Missed Lines	%
src/angular/app.ts	1	85.84%

Totals
Change from base Build 118:	-0.01%
Covered Lines:	825
Relevant Lines:	1003

---

💛 - Coveralls

[coveralls]

Pull Request Test Coverage Report for Build 131

• 20 of 32 (62.5%) changed or added relevant lines in 7 files are covered.
• 1 unchanged line in 1 file lost coverage.
• Overall coverage decreased (-0.01%) to 77.139%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/native/network.ts	1	3	33.33%
src/native/nfc.ts	1	11	9.09%

Files with Coverage Reduction	New Missed Lines	%
src/angular/app.ts	1	85.84%

Totals
Change from base Build 118:	-0.01%
Covered Lines:	825
Relevant Lines:	1003

---

💛 - Coveralls